How to use _write method in Cypress

...506                return this;507            },508509            _writeLine: function (s) {510                this._write(s)._write("\n");511                return this;512            },513514            _writeIndents: function () {515                for (var i = 0; i < this._indent; i++) {516                    this._write(" ");517                }518519                for (var i = 0; i < this._indentLevel; i++) {520                    this._write("    ");521                }522                return this;523            },524525            generate: function (params, jscexAst) {526                this._buffer = [];527528                this._writeLine("(function (" + params.join(", ") + ") {");529                this._indentLevel++;530531                this._writeIndents()532                    ._writeLine("var " + this._builderVar + " = Jscex.builders[" + stringify(this._builderName) + "];");533534                this._writeIndents()535                    ._writeLine("return " + this._builderVar + ".Start(this,");536                this._indentLevel++;537538                this._pos = { };539540                this._writeIndents()541                    ._visitJscex(jscexAst)542                    ._writeLine();543                this._indentLevel--;544545                this._writeIndents()546                    ._writeLine(");");547                this._indentLevel--;548549                this._writeIndents()550                    ._write("})");551552                return this._buffer.join("");553            },554555            _visitJscex: function (ast) {556                this._jscexVisitors[ast.type].call(this, ast);557                return this;558            },559560            _visitRaw: function (ast) {561                var type = ast[0];562563                function throwUnsupportedError() {564                    throw new Error('"' + type + '" is not currently supported.');565                }566567                var visitor = this._rawVisitors[type];568569                if (visitor) {570                    visitor.call(this, ast);571                } else {572                    throwUnsupportedError();573                }574575                return this;576            },577578            _visitJscexStatements: function (statements) {579                for (var i = 0; i < statements.length; i++) {580                    var stmt = statements[i];581582                    if (stmt.type == "raw" || stmt.type == "if" || stmt.type == "switch") {583                        this._writeIndents()584                            ._visitJscex(stmt)._writeLine();585                    } else if (stmt.type == "delay") {586                        this._visitJscexStatements(stmt.stmts);587                    } else {588                        this._writeIndents()589                            ._write("return ")._visitJscex(stmt)._writeLine(";");590                    }591                }592            },593594            _visitRawStatements: function (statements) {595                for (var i = 0; i < statements.length; i++) {596                    var s = statements[i];597598                    this._writeIndents()599                        ._visitRaw(s)._writeLine();600601                    switch (s[0]) {602                        case "break":603                        case "return":604                        case "continue":605                        case "throw":606                            return;607                    }608                }609            },610611            _visitRawBody: function (body) {612                if (body[0] == "block") {613                    this._visitRaw(body);614                } else {615                    this._writeLine();616                    this._indentLevel++;617618                    this._writeIndents()619                        ._visitRaw(body);620                    this._indentLevel--;621                }622623                return this;624            },625626            _visitRawFunction: function (ast) {627                var funcName = ast[1] || "";628                var args = ast[2];629                var statements = ast[3];630                631                this._writeLine("function " + funcName + "(" + args.join(", ") + ") {")632                this._indentLevel++;633634                var currInFunction = this._pos.inFunction;635                this._pos.inFunction = true;636637                this._visitRawStatements(statements);638                this._indentLevel--;639640                this._pos.inFunction = currInFunction;641642                this._writeIndents()643                    ._write("}");644            },645646            _jscexVisitors: {647                "delay": function (ast) {648                    if (ast.stmts.length == 1) {649                        var subStmt = ast.stmts[0];650                        switch (subStmt.type) {651                            case "delay":652                            case "combine":653                            case "normal":654                            case "break":655                            case "continue":656                            case "loop":657                            case "try":658                                this._visitJscex(subStmt);659                                return;660                            case "return":661                                if (!subStmt.stmt[1]) {662                                    this._visitJscex(subStmt);663                                    return;664                                }665                        }666                    }667668                    this._writeLine(this._builderVar + ".Delay(function () {");669                    this._indentLevel++;670671                    this._visitJscexStatements(ast.stmts);672                    this._indentLevel--;673674                    this._writeIndents()675                        ._write("})");676                },677678                "combine": function (ast) {679                    this._writeLine(this._builderVar + ".Combine(");680                    this._indentLevel++;681682                    this._writeIndents()683                        ._visitJscex(ast.first)._writeLine(",");684                    this._writeIndents()685                        ._visitJscex(ast.second)._writeLine();686                    this._indentLevel--;687688                    this._writeIndents()689                        ._write(")");690                },691692                "loop": function (ast) {693                    this._writeLine(this._builderVar + ".Loop(");694                    this._indentLevel++;695696                    if (ast.condition) {697                        this._writeIndents()698                            ._writeLine("function () {");699                        this._indentLevel++;700701                        this._writeIndents()702                            ._write("return ")._visitRaw(ast.condition)._writeLine(";");703                        this._indentLevel--;704705                        this._writeIndents()706                            ._writeLine("},");707                    } else {708                        this._writeIndents()._writeLine("null,");709                    }710711                    if (ast.update) {712                        this._writeIndents()713                            ._writeLine("function () {");714                        this._indentLevel++;715716                        this._writeIndents()717                            ._visitRaw(ast.update)._writeLine(";");718                        this._indentLevel--;719720                        this._writeIndents()721                            ._writeLine("},");722                    } else {723                        this._writeIndents()._writeLine("null,");724                    }725726                    this._writeIndents()727                        ._visitJscex(ast.bodyStmt)._writeLine(",");728729                    this._writeIndents()730                        ._writeLine(ast.bodyFirst);731                    this._indentLevel--;732733                    this._writeIndents()734                        ._write(")");735                },736737                "raw": function (ast) {738                    this._visitRaw(ast.stmt);739                },740741                "bind": function (ast) {742                    var info = ast.info;743                    this._write(this._builderVar + ".Bind(")._visitRaw(info.expression)._writeLine(", function (" + info.argName + ") {");744                    this._indentLevel++;745746                    if (info.assignee == "return") {747                        this._writeIndents()748                            ._writeLine("return " + this._builderVar + ".Return(" + info.argName + ");");749                    } else {750                        if (info.assignee) {751                            this._writeIndents()752                                ._visitRaw(info.assignee)._writeLine(" = " + info.argName + ";");753                        }754755                        this._visitJscexStatements(ast.stmts);756                    }757                    this._indentLevel--;758759                    this._writeIndents()760                        ._write("})");761                },762763                "if": function (ast) {764765                    for (var i = 0; i < ast.conditionStmts.length; i++) {766                        var stmt = ast.conditionStmts[i];767                        768                        this._write("if (")._visitRaw(stmt.cond)._writeLine(") {");769                        this._indentLevel++;770771                        this._visitJscexStatements(stmt.stmts);772                        this._indentLevel--;773774                        this._writeIndents()775                            ._write("} else ");776                    }777778                    this._writeLine("{");779                    this._indentLevel++;780781                    if (ast.elseStmts) {782                        this._visitJscexStatements(ast.elseStmts);783                    } else {784                        this._writeIndents()785                            ._writeLine("return " + this._builderVar + ".Normal();");786                    }787788                    this._indentLevel--;789790                    this._writeIndents()791                        ._write("}");792                },793794                "switch": function (ast) {795                    this._write("switch (")._visitRaw(ast.item)._writeLine(") {");796                    this._indentLevel++;797798                    for (var i = 0; i < ast.caseStmts.length; i++) {799                        var caseStmt = ast.caseStmts[i];800801                        if (caseStmt.item) {802                            this._writeIndents()803                                ._write("case ")._visitRaw(caseStmt.item)._writeLine(":");804                        } else {805                            this._writeIndents()._writeLine("default:");806                        }807                        this._indentLevel++;808809                        this._visitJscexStatements(caseStmt.stmts);810                        this._indentLevel--;811                    }812813                    this._writeIndents()814                        ._write("}");815                },816817                "try": function (ast) {818                    this._writeLine(this._builderVar + ".Try(");819                    this._indentLevel++;820821                    this._writeIndents()822                        ._visitJscex(ast.bodyStmt)._writeLine(",");823824                    if (ast.catchStmts) {825                        this._writeIndents()826                            ._writeLine("function (" + ast.exVar + ") {");827                        this._indentLevel++;828829                        this._visitJscexStatements(ast.catchStmts);830                        this._indentLevel--;831832                        this._writeIndents()833                            ._writeLine("},");834                    } else {835                        this._writeIndents()836                            ._writeLine("null,");837                    }838839                    if (ast.finallyStmt) {840                        this._writeIndents()841                            ._visitJscex(ast.finallyStmt)._writeLine();842                    } else {843                        this._writeIndents()844                            ._writeLine("null");845                    }846                    this._indentLevel--;847848                    this._writeIndents()849                        ._write(")");850                },851852                "normal": function (ast) {853                    this._write(this._builderVar + ".Normal()");854                },855856                "throw": function (ast) {857                    this._write(this._builderVar + ".Throw(")._visitRaw(ast.stmt[1])._write(")");858                },859860                "break": function (ast) {861                    this._write(this._builderVar + ".Break()");862                },863864                "continue": function (ast) {865                    this._write(this._builderVar + ".Continue()");866                },867868                "return": function (ast) {869                    this._write(this._builderVar + ".Return(");870                    if (ast.stmt[1]) this._visitRaw(ast.stmt[1]);871                    this._write(")");872                }873            },874875            _rawVisitors: {876                "var": function (ast) {877                    this._write("var ");878879                    var items = ast[1];880                    for (var i = 0; i < items.length; i++) {881                        this._write(items[i][0]);882                        if (items[i].length > 1) {883                            this._write(" = ")._visitRaw(items[i][1]);884                        }885                        if (i < items.length - 1) this._write(", ");886                    }887888                    this._write(";");889                },890891                "seq": function (ast) {892                    for (var i = 1; i < ast.length; i++) {893                        this._visitRaw(ast[i]);894                        if (i < ast.length - 1) this._write(", "); 895                    }896                },897898                "binary": function (ast) {899                    var op = ast[1], left = ast[2], right = ast[3];900901                    function needBracket(item) {902                        var type = item[0];903                        return !(type == "num" || type == "name" || type == "dot");904                    }905906                    if (needBracket(left)) {907                        this._write("(")._visitRaw(left)._write(") ");908                    } else {909                        this._visitRaw(left)._write(" ");910                    }911912                    this._write(op);913914                    if (needBracket(right)) {915                        this._write(" (")._visitRaw(right)._write(")");916                    } else {917                        this._write(" ")._visitRaw(right);918                    }919                },920921                "sub": function (ast) {922                    var prop = ast[1], index = ast[2];923924                    function needBracket() {925                        return !(prop[0] == "name")926                    }927928                    if (needBracket()) {929                        this._write("(")._visitRaw(prop)._write(")[")._visitRaw(index)._write("]");930                    } else {931                        this._visitRaw(prop)._write("[")._visitRaw(index)._write("]");932                    }933                },934935                "unary-postfix": function (ast) {936                    var op = ast[1];937                    var item = ast[2];938                    this._visitRaw(item)._write(op);939                },940941                "unary-prefix": function (ast) {942                    var op = ast[1];943                    var item = ast[2];944                    this._write(op);945                    if (op == "typeof") {946                        this._write("(")._visitRaw(item)._write(")");947                    } else {948                        this._visitRaw(item);949                    }950                },951952                "assign": function (ast) {953                    var op = ast[1];954                    var name = ast[2];955                    var value = ast[3];956957                    this._visitRaw(name);958                    if ((typeof op) == "string") {959                        this._write(" " + op + "= ");960                    } else {961                        this._write(" = ");962                    }963                    this._visitRaw(value);964                },965966                "stat": function (ast) {967                    this._visitRaw(ast[1])._write(";");968                },969970                "dot": function (ast) {971                    function needBracket() {972                        var leftOp = ast[1][0];973                        return !(leftOp == "dot" || leftOp == "name");974                    }975976                    if (needBracket()) {977                        this._write("(")._visitRaw(ast[1])._write(").")._write(ast[2]);978                    } else {979                        this._visitRaw(ast[1])._write(".")._write(ast[2]);980                    }981                },982983                "new": function (ast) {984                    var ctor = ast[1];985986                    this._write("new ")._visitRaw(ctor)._write("(");987988                    var args = ast[2];989                    for (var i = 0, len = args.length; i < len; i++) {990                        this._visitRaw(args[i]);991                        if (i < len - 1) this._write(", ");992                    }993994                    this._write(")");995                },996997                "call": function (ast) {998                999                    if (_isJscexPattern(ast)) {1000                        var indent = this._indent + this._indentLevel * 4;1001                        var newCode = _compileJscexPattern(ast, indent);1002                        this._write(newCode);1003                    } else {10041005                        var invalidBind = (ast[1][0] == "name") && (ast[1][1] == this._binder);1006                        if (invalidBind) {1007                            this._pos = { inFunction: true };1008                            this._buffer = [];1009                        }10101011                        this._visitRaw(ast[1])._write("(");10121013                        var args = ast[2];1014                        for (var i = 0; i < args.length; i++) {1015                            this._visitRaw(args[i]);1016                            if (i < args.length - 1) this._write(", ");1017                        }10181019                        this._write(")");10201021                        if (invalidBind) {1022                            throw ("Invalid bind operation: " + this._buffer.join(""));1023                        }1024                    }1025                },10261027                "name": function (ast) {1028                    this._write(ast[1]);1029                },10301031                "object": function (ast) {1032                    var items = ast[1];1033                    if (items.length <= 0) {1034                        this._write("{ }");1035                    } else {1036                        this._writeLine("{");1037                        this._indentLevel++;1038                        1039                        for (var i = 0; i < items.length; i++) {1040                            this._writeIndents()1041                                ._write(stringify(items[i][0]) + ": ")1042                                ._visitRaw(items[i][1]);1043                            1044                            if (i < items.length - 1) {1045                                this._writeLine(",");1046                            } else {1047                                this._writeLine("");1048                            }1049                        }1050                        1051                        this._indentLevel--;1052                        this._writeIndents()._write("}");1053                    }1054                },10551056                "array": function (ast) {1057                    this._write("[");10581059                    var items = ast[1];1060                    for (var i = 0; i < items.length; i++) {1061                        this._visitRaw(items[i]);1062                        if (i < items.length - 1) this._write(", ");1063                    }10641065                    this._write("]");1066                },10671068                "num": function (ast) {1069                    this._write(ast[1]);1070                },10711072                "regexp": function (ast) {1073                    this._write("/" + ast[1] + "/" + ast[2]);1074                },10751076                "string": function (ast) {1077                    this._write(stringify(ast[1]));1078                },10791080                "function": function (ast) {1081                    this._visitRawFunction(ast);1082                },10831084                "defun": function (ast) {1085                    this._visitRawFunction(ast);1086                },10871088                "return": function (ast) {1089                    if (this._pos.inFunction) {1090                        this._write("return");1091                        var value = ast[1];1092                        if (value) this._write(" ")._visitRaw(value);1093                        this._write(";");1094                    } else {1095                        this._write("return ")._visitJscex({ type: "return", stmt: ast })._write(";");1096                    }1097                },1098                1099                "for": function (ast) {1100                    this._write("for (");11011102                    var setup = ast[1];1103                    if (setup) {1104                        this._visitRaw(setup);1105                        if (setup[0] != "var") {1106                            this._write("; ");1107                        } else {1108                            this._write(" ");1109                        }1110                    } else {1111                        this._write("; ");1112                    }11131114                    var condition = ast[2];1115                    if (condition) this._visitRaw(condition);1116                    this._write("; ");11171118                    var update = ast[3];1119                    if (update) this._visitRaw(update);1120                    this._write(") ");11211122                    var currInLoop = this._pos.inLoop;1123                    this._pos.inLoop = true;11241125                    var body = ast[4];1126                    this._visitRawBody(body);11271128                    this._pos.inLoop = currInLoop;1129                },11301131                "for-in": function (ast) {1132                    this._write("for (");11331134                    var declare = ast[1];1135                    if (declare[0] == "var") { // declare == ["var", [["m"]]]1136                        this._write("var " + declare[1][0][0]);1137                    } else {1138                        this._visitRaw(declare);1139                    }1140                    1141                    this._write(" in ")._visitRaw(ast[3])._write(") ");11421143                    var body = ast[4];1144                    this._visitRawBody(body);1145                },11461147                "block": function (ast) {1148                    this._writeLine("{")1149                    this._indentLevel++;11501151                    this._visitRawStatements(ast[1]);1152                    this._indentLevel--;11531154                    this._writeIndents()1155                        ._write("}");1156                },11571158                "while": function (ast) {1159                    var condition = ast[1];1160                    var body = ast[2];11611162                    var currInLoop = this._pos.inLoop1163                    this._pos.inLoop = true;11641165                    this._write("while (")._visitRaw(condition)._write(") ")._visitRawBody(body);11661167                    this._pos.inLoop = currInLoop;1168                },11691170                "do": function (ast) {1171                    var condition = ast[1];1172                    var body = ast[2];11731174                    var currInLoop = this._pos.inLoop;1175                    this._pos.inLoop = true;11761177                    this._write("do ")._visitRawBody(body);11781179                    this._pos.inLoop = currInLoop;11801181                    if (body[0] == "block") {1182                        this._write(" ");1183                    } else {1184                        this._writeLine()._writeIndents();1185                    }11861187                    this._write("while (")._visitRaw(condition)._write(");");1188                },11891190                "if": function (ast) {1191                    var condition = ast[1];1192                    var thenPart = ast[2];11931194                    this._write("if (")._visitRaw(condition)._write(") ")._visitRawBody(thenPart);11951196                    var elsePart = ast[3];1197                    if (elsePart) {1198                        if (thenPart[0] == "block") {1199                            this._write(" ");1200                        } else {1201                            this._writeLine("")1202                                ._writeIndents();1203                        }12041205                        if (elsePart[0] == "if") {1206                            this._write("else ")._visitRaw(elsePart);1207                        } else {1208                            this._write("else ")._visitRawBody(elsePart);1209                        }1210                    }1211                },12121213                "break": function (ast) {1214                    if (this._pos.inLoop || this._pos.inSwitch) {1215                        this._write("break;");1216                    } else {1217                        this._write("return ")._visitJscex({ type: "break", stmt: ast })._write(";");1218                    }1219                },12201221                "continue": function (ast) {1222                    if (this._pos.inLoop) {1223                        this._write("continue;");1224                    } else {1225                        this._write("return ")._visitJscex({ type: "continue", stmt: ast })._write(";");1226                    }1227                },12281229                "throw": function (ast) {1230                    var pos = this._pos;1231                    if (pos.inTry || pos.inFunction) {1232                        this._write("throw ")._visitRaw(ast[1])._write(";");1233                    } else {1234                        this._write("return ")._visitJscex({ type: "throw", stmt: ast })._write(";");1235                    }1236                },12371238                "conditional": function (ast) {1239                    this._write("(")._visitRaw(ast[1])._write(") ? (")._visitRaw(ast[2])._write(") : (")._visitRaw(ast[3])._write(")");1240                },12411242                "try": function (ast) {12431244                    this._writeLine("try {");1245                    this._indentLevel++;12461247                    var currInTry = this._pos.inTry;1248                    this._pos.inTry = true;12491250                    this._visitRawStatements(ast[1]);1251                    this._indentLevel--;12521253                    this._pos.inTry = currInTry;12541255                    var catchClause = ast[2];1256                    var finallyStatements = ast[3];12571258                    if (catchClause) {1259                        this._writeIndents()1260                            ._writeLine("} catch (" + catchClause[0] + ") {")1261                        this._indentLevel++;12621263                        this._visitRawStatements(catchClause[1]);1264                        this._indentLevel--;1265                    }12661267                    if (finallyStatements) {1268                        this._writeIndents()1269                            ._writeLine("} finally {");1270                        this._indentLevel++;12711272                        this._visitRawStatements(finallyStatements);1273                        this._indentLevel--;1274                    }                12751276                    this._writeIndents()1277                        ._write("}");1278                },12791280                "switch": function (ast) {1281                    this._write("switch (")._visitRaw(ast[1])._writeLine(") {");1282                    this._indentLevel++;12831284                    var currInSwitch = this._pos.inSwitch;1285                    this._pos.inSwitch = true;12861287                    var cases = ast[2];1288                    for (var i = 0; i < cases.length; i++) {1289                        var c = cases[i];1290                        this._writeIndents();12911292                        if (c[0]) {1293                            this._write("case ")._visitRaw(c[0])._writeLine(":");1294                        } else {1295                            this._writeLine("default:");1296                        }1297                        this._indentLevel++;12981299                        this._visitRawStatements(c[1]);1300                        this._indentLevel--;1301                    }1302                    this._indentLevel--;13031304                    this._pos.inSwitch = currInSwitch;13051306                    this._writeIndents()1307                        ._write("}");1308                }1309            }1310        }13111312        function _isJscexPattern(ast) {1313            if (ast[0] != "call") return false;1314            1315            var evalName = ast[1];1316            if (evalName[0] != "name" || evalName[1] != "eval") return false;13171318            var compileCall = ast[2][0];1319            if (!compileCall || compileCall[0] != "call") return false;13201321            var compileMethod = compileCall[1];
...

...36        self._single_func = single_line_functions37        self._do_indent = True38        self._indent = 039        self._dispatch(tree)40        self._write("\n")41        self.f.flush()42    #########################################################################43    # Unparser private interface.44    #########################################################################45    ### format, output, and dispatch methods ################################46    def _fill(self, text = ""):47        "Indent a piece of text, according to the current indentation level"48        if self._do_indent:49            self._write("\n"+"    "*self._indent + text)50        else:51            self._write(text)52    def _write(self, text):53        "Append a piece of text to the current line."54        self.f.write(text)55    def _enter(self):56        "Print ':', and increase the indentation."57        self._write(": ")58        self._indent += 159    def _leave(self):60        "Decrease the indentation level."61        self._indent -= 162    def _dispatch(self, tree):63        "_dispatcher function, _dispatching tree type T to method _T."64        if isinstance(tree, list):65            for t in tree:66                self._dispatch(t)67            return68        meth = getattr(self, "_"+tree.__class__.__name__)69        if tree.__class__.__name__ == 'NoneType' and not self._do_indent:70            return71        meth(tree)72    #########################################################################73    # compiler.ast unparsing methods.74    #75    # There should be one method per concrete grammar type. They are76    # organized in alphabetical order.77    #########################################################################78    def _Add(self, t):79        self.__binary_op(t, '+')80    def _And(self, t):81        self._write(" (")82        for i, node in enumerate(t.nodes):83            self._dispatch(node)84            if i != len(t.nodes)-1:85                self._write(") and (")86        self._write(")")87    def _AssAttr(self, t):88        """ Handle assigning an attribute of an object89        """90        self._dispatch(t.expr)91        self._write('.'+t.attrname)92    def _Assign(self, t):93        """ Expression Assignment such as "a = 1".94            This only handles assignment in expressions.  Keyword assignment95            is handled separately.96        """97        self._fill()98        for target in t.nodes:99            self._dispatch(target)100            self._write(" = ")101        self._dispatch(t.expr)102        if not self._do_indent:103            self._write('; ')104    def _AssName(self, t):105        """ Name on left hand side of expression.106            Treat just like a name on the right side of an expression.107        """108        self._Name(t)109    def _AssTuple(self, t):110        """ Tuple on left hand side of an expression.111        """112        # _write each elements, separated by a comma.113        for element in t.nodes[:-1]:114            self._dispatch(element)115            self._write(", ")116        # Handle the last one without writing comma117        last_element = t.nodes[-1]118        self._dispatch(last_element)119    def _AugAssign(self, t):120        """ +=,-=,*=,/=,**=, etc. operations121        """122        self._fill()123        self._dispatch(t.node)124        self._write(' '+t.op+' ')125        self._dispatch(t.expr)126        if not self._do_indent:127            self._write(';')128    def _Bitand(self, t):129        """ Bit and operation.130        """131        for i, node in enumerate(t.nodes):132            self._write("(")133            self._dispatch(node)134            self._write(")")135            if i != len(t.nodes)-1:136                self._write(" & ")137    def _Bitor(self, t):138        """ Bit or operation139        """140        for i, node in enumerate(t.nodes):141            self._write("(")142            self._dispatch(node)143            self._write(")")144            if i != len(t.nodes)-1:145                self._write(" | ")146    def _CallFunc(self, t):147        """ Function call.148        """149        self._dispatch(t.node)150        self._write("(")151        comma = False152        for e in t.args:153            if comma: self._write(", ")154            else: comma = True155            self._dispatch(e)156        if t.star_args:157            if comma: self._write(", ")158            else: comma = True159            self._write("*")160            self._dispatch(t.star_args)161        if t.dstar_args:162            if comma: self._write(", ")163            else: comma = True164            self._write("**")165            self._dispatch(t.dstar_args)166        self._write(")")167    def _Compare(self, t):168        self._dispatch(t.expr)169        for op, expr in t.ops:170            self._write(" " + op + " ")171            self._dispatch(expr)172    def _Const(self, t):173        """ A constant value such as an integer value, 3, or a string, "hello".174        """175        self._dispatch(t.value)176    def _Decorators(self, t):177        """ Handle function decorators (eg. @has_units)178        """179        for node in t.nodes:180            self._dispatch(node)181    def _Dict(self, t):182        self._write("{")183        for  i, (k, v) in enumerate(t.items):184            self._dispatch(k)185            self._write(": ")186            self._dispatch(v)187            if i < len(t.items)-1:188                self._write(", ")189        self._write("}")190    def _Discard(self, t):191        """ Node for when return value is ignored such as in "foo(a)".192        """193        self._fill()194        self._dispatch(t.expr)195    def _Div(self, t):196        self.__binary_op(t, '/')197    def _Ellipsis(self, t):198        self._write("...")199    def _From(self, t):200        """ Handle "from xyz import foo, bar as baz".201        """202        # fixme: Are From and ImportFrom handled differently?203        self._fill("from ")204        self._write(t.modname)205        self._write(" import ")206        for i, (name,asname) in enumerate(t.names):207            if i != 0:208                self._write(", ")209            self._write(name)210            if asname is not None:211                self._write(" as "+asname)212    def _Function(self, t):213        """ Handle function definitions214        """215        if t.decorators is not None:216            self._fill("@")217            self._dispatch(t.decorators)218        self._fill("def "+t.name + "(")219        defaults = [None] * (len(t.argnames) - len(t.defaults)) + list(t.defaults)220        for i, arg in enumerate(zip(t.argnames, defaults)):221            self._write(arg[0])222            if arg[1] is not None:223                self._write('=')224                self._dispatch(arg[1])225            if i < len(t.argnames)-1:226                self._write(', ')227        self._write(")")228        if self._single_func:229            self._do_indent = False230        self._enter()231        self._dispatch(t.code)232        self._leave()233        self._do_indent = True234    def _Getattr(self, t):235        """ Handle getting an attribute of an object236        """237        if isinstance(t.expr, (Div, Mul, Sub, Add)):238            self._write('(')239            self._dispatch(t.expr)240            self._write(')')241        else:242            self._dispatch(t.expr)243            244        self._write('.'+t.attrname)245        246    def _If(self, t):247        self._fill()248        249        for i, (compare,code) in enumerate(t.tests):250            if i == 0:251                self._write("if ")252            else:253                self._write("elif ")254            self._dispatch(compare)255            self._enter()256            self._fill()257            self._dispatch(code)258            self._leave()259            self._write("\n")260        if t.else_ is not None:261            self._write("else")262            self._enter()263            self._fill()264            self._dispatch(t.else_)265            self._leave()266            self._write("\n")267            268    def _IfExp(self, t):269        self._dispatch(t.then)270        self._write(" if ")271        self._dispatch(t.test)272        if t.else_ is not None:273            self._write(" else (")274            self._dispatch(t.else_)275            self._write(")")276    def _Import(self, t):277        """ Handle "import xyz.foo".278        """279        self._fill("import ")280        281        for i, (name,asname) in enumerate(t.names):282            if i != 0:283                self._write(", ")284            self._write(name)285            if asname is not None:286                self._write(" as "+asname)287    def _Keyword(self, t):288        """ Keyword value assignment within function calls and definitions.289        """290        self._write(t.name)291        self._write("=")292        self._dispatch(t.expr)293        294    def _List(self, t):295        self._write("[")296        for  i,node in enumerate(t.nodes):297            self._dispatch(node)298            if i < len(t.nodes)-1:299                self._write(", ")300        self._write("]")301    def _Module(self, t):302        if t.doc is not None:303            self._dispatch(t.doc)304        self._dispatch(t.node)305    def _Mul(self, t):306        self.__binary_op(t, '*')307    def _Name(self, t):308        self._write(t.name)309    def _NoneType(self, t):310        self._write("None")311        312    def _Not(self, t):313        self._write('not (')314        self._dispatch(t.expr)315        self._write(')')316        317    def _Or(self, t):318        self._write(" (")319        for i, node in enumerate(t.nodes):320            self._dispatch(node)321            if i != len(t.nodes)-1:322                self._write(") or (")323        self._write(")")324                325    def _Pass(self, t):326        self._write("pass\n")327    def _Printnl(self, t):328        self._fill("print ")329        if t.dest:330            self._write(">> ")331            self._dispatch(t.dest)332            self._write(", ")333        comma = False334        for node in t.nodes:335            if comma: self._write(', ')336            else: comma = True337            self._dispatch(node)338    def _Power(self, t):339        self.__binary_op(t, '**')340    def _Return(self, t):341        self._fill("return ")342        if t.value:343            if isinstance(t.value, Tuple):344                text = ', '.join([ name.name for name in t.value.asList() ])345                self._write(text)346            else:347                self._dispatch(t.value)348            if not self._do_indent:349                self._write('; ')350    def _Slice(self, t):351        self._dispatch(t.expr)352        self._write("[")353        if t.lower:354            self._dispatch(t.lower)355        self._write(":")356        if t.upper:357            self._dispatch(t.upper)358        #if t.step:359        #    self._write(":")360        #    self._dispatch(t.step)361        self._write("]")362    def _Sliceobj(self, t):363        for i, node in enumerate(t.nodes):364            if i != 0:365                self._write(":")366            if not (isinstance(node, Const) and node.value is None):367                self._dispatch(node)368    def _Stmt(self, tree):369        for node in tree.nodes:370            self._dispatch(node)371    def _Sub(self, t):372        self.__binary_op(t, '-')373    def _Subscript(self, t):374        self._dispatch(t.expr)375        self._write("[")376        for i, value in enumerate(t.subs):377            if i != 0:378                self._write(",")379            self._dispatch(value)380        self._write("]")381    def _TryExcept(self, t):382        self._fill("try")383        self._enter()384        self._dispatch(t.body)385        self._leave()386        for handler in t.handlers:387            self._fill('except ')388            self._dispatch(handler[0])389            if handler[1] is not None:390                self._write(', ')391                self._dispatch(handler[1])392            self._enter()393            self._dispatch(handler[2])394            self._leave()395            396        if t.else_:397            self._fill("else")398            self._enter()399            self._dispatch(t.else_)400            self._leave()401    def _Tuple(self, t):402        if not t.nodes:403            # Empty tuple.404            self._write("()")405        else:406            self._write("(")407            # _write each elements, separated by a comma.408            for element in t.nodes[:-1]:409                self._dispatch(element)410                self._write(", ")411            # Handle the last one without writing comma412            last_element = t.nodes[-1]413            self._dispatch(last_element)414            self._write(")")415            416    def _UnaryAdd(self, t):417        self._write("+")418        self._dispatch(t.expr)419        420    def _UnarySub(self, t):421        self._write("-")422        self._dispatch(t.expr)        423    def _With(self, t):424        self._fill('with ')425        self._dispatch(t.expr)426        if t.vars:427            self._write(' as ')428            self._dispatch(t.vars.name)429        self._enter()430        self._dispatch(t.body)431        self._leave()432        self._write('\n')433        434    def _int(self, t):435        self._write(repr(t))436    def __binary_op(self, t, symbol):437        # Check if parenthesis are needed on left side and then dispatch438        has_paren = False439        left_class = str(t.left.__class__)440        if (left_class in op_precedence.keys() and441            op_precedence[left_class] < op_precedence[str(t.__class__)]):442            has_paren = True443        if has_paren:444            self._write('(')445        self._dispatch(t.left)446        if has_paren:447            self._write(')')448        # Write the appropriate symbol for operator449        self._write(symbol)450        # Check if parenthesis are needed on the right side and then dispatch451        has_paren = False452        right_class = str(t.right.__class__)453        if (right_class in op_precedence.keys() and454            op_precedence[right_class] < op_precedence[str(t.__class__)]):455            has_paren = True456        if has_paren:457            self._write('(')458        self._dispatch(t.right)459        if has_paren:460            self._write(')')461    def _float(self, t):462        # if t is 0.1, str(t)->'0.1' while repr(t)->'0.1000000000001'463        # We prefer str here.464        self._write(str(t))465    def _str(self, t):466        self._write(repr(t))467        468    def _tuple(self, t):469        self._write(str(t))470    #########################################################################471    # These are the methods from the _ast modules unparse.472    #473    # As our needs to handle more advanced code increase, we may want to474    # modify some of the methods below so that they work for compiler.ast.475    #########################################################################476#    # stmt477#    def _Expr(self, tree):478#        self._fill()479#        self._dispatch(tree.value)480#481#    def _Import(self, t):482#        self._fill("import ")483#        first = True484#        for a in t.names:485#            if first:486#                first = False487#            else:488#                self._write(", ")489#            self._write(a.name)490#            if a.asname:491#                self._write(" as "+a.asname)492#493##    def _ImportFrom(self, t):494##        self._fill("from ")495##        self._write(t.module)496##        self._write(" import ")497##        for i, a in enumerate(t.names):498##            if i == 0:499##                self._write(", ")500##            self._write(a.name)501##            if a.asname:502##                self._write(" as "+a.asname)503##        # XXX(jpe) what is level for?504##505#506#    def _Break(self, t):507#        self._fill("break")508#509#    def _Continue(self, t):510#        self._fill("continue")511#512#    def _Delete(self, t):513#        self._fill("del ")514#        self._dispatch(t.targets)515#516#    def _Assert(self, t):517#        self._fill("assert ")518#        self._dispatch(t.test)519#        if t.msg:520#            self._write(", ")521#            self._dispatch(t.msg)522#523#    def _Exec(self, t):524#        self._fill("exec ")525#        self._dispatch(t.body)526#        if t.globals:527#            self._write(" in ")528#            self._dispatch(t.globals)529#        if t.locals:530#            self._write(", ")531#            self._dispatch(t.locals)532#533#    def _Print(self, t):534#        self._fill("print ")535#        do_comma = False536#        if t.dest:537#            self._write(">>")538#            self._dispatch(t.dest)539#            do_comma = True540#        for e in t.values:541#            if do_comma:self._write(", ")542#            else:do_comma=True543#            self._dispatch(e)544#        if not t.nl:545#            self._write(",")546#547#    def _Global(self, t):548#        self._fill("global")549#        for i, n in enumerate(t.names):550#            if i != 0:551#                self._write(",")552#            self._write(" " + n)553#554#    def _Yield(self, t):555#        self._fill("yield")556#        if t.value:557#            self._write(" (")558#            self._dispatch(t.value)559#            self._write(")")560#561#    def _Raise(self, t):562#        self._fill('raise ')563#        if t.type:564#            self._dispatch(t.type)565#        if t.inst:566#            self._write(", ")567#            self._dispatch(t.inst)568#        if t.tback:569#            self._write(", ")570#            self._dispatch(t.tback)571#572#573#    def _TryFinally(self, t):574#        self._fill("try")575#        self._enter()576#        self._dispatch(t.body)577#        self._leave()578#579#        self._fill("finally")580#        self._enter()581#        self._dispatch(t.finalbody)582#        self._leave()583#584#    def _excepthandler(self, t):585#        self._fill("except ")586#        if t.type:587#            self._dispatch(t.type)588#        if t.name:589#            self._write(", ")590#            self._dispatch(t.name)591#        self._enter()592#        self._dispatch(t.body)593#        self._leave()594#595#    def _ClassDef(self, t):596#        self._write("\n")597#        self._fill("class "+t.name)598#        if t.bases:599#            self._write("(")600#            for a in t.bases:601#                self._dispatch(a)602#                self._write(", ")603#            self._write(")")604#        self._enter()605#        self._dispatch(t.body)606#        self._leave()607#608#    def _FunctionDef(self, t):609#        self._write("\n")610#        for deco in t.decorators:611#            self._fill("@")612#            self._dispatch(deco)613#        self._fill("def "+t.name + "(")614#        self._dispatch(t.args)615#        self._write(")")616#        self._enter()617#        self._dispatch(t.body)618#        self._leave()619#620#    def _For(self, t):621#        self._fill("for ")622#        self._dispatch(t.target)623#        self._write(" in ")624#        self._dispatch(t.iter)625#        self._enter()626#        self._dispatch(t.body)627#        self._leave()628#        if t.orelse:629#            self._fill("else")630#            self._enter()631#            self._dispatch(t.orelse)632#            self._leave633#634#    def _While(self, t):635#        self._fill("while ")636#        self._dispatch(t.test)637#        self._enter()638#        self._dispatch(t.body)639#        self._leave()640#        if t.orelse:641#            self._fill("else")642#            self._enter()643#            self._dispatch(t.orelse)644#            self._leave645#646#    # expr647#    def _Str(self, tree):648#        self._write(repr(tree.s))649##650#    def _Repr(self, t):651#        self._write("`")652#        self._dispatch(t.value)653#        self._write("`")654#655#    def _Num(self, t):656#        self._write(repr(t.n))657#658#    def _ListComp(self, t):659#        self._write("[")660#        self._dispatch(t.elt)661#        for gen in t.generators:662#            self._dispatch(gen)663#        self._write("]")664#665#    def _GeneratorExp(self, t):666#        self._write("(")667#        self._dispatch(t.elt)668#        for gen in t.generators:669#            self._dispatch(gen)670#        self._write(")")671#672#    def _comprehension(self, t):673#        self._write(" for ")674#        self._dispatch(t.target)675#        self._write(" in ")676#        self._dispatch(t.iter)677#        for if_clause in t.ifs:678#            self._write(" if ")679#            self._dispatch(if_clause)680#681#    def _IfExp(self, t):682#        self._dispatch(t.body)683#        self._write(" if ")684#        self._dispatch(t.test)685#        if t.orelse:686#            self._write(" else ")687#            self._dispatch(t.orelse)688#689#    unop = {"Invert":"~", "Not": "not", "UAdd":"+", "USub":"-"}690#    def _UnaryOp(self, t):691#        self._write(self.unop[t.op.__class__.__name__])692#        self._write("(")693#        self._dispatch(t.operand)694#        self._write(")")695#696#    binop = { "Add":"+", "Sub":"-", "Mult":"*", "Div":"/", "Mod":"%",697#                    "LShift":">>", "RShift":"<<", "BitOr":"|", "BitXor":"^", "BitAnd":"&",698#                    "FloorDiv":"//", "Pow": "**"}699#    def _BinOp(self, t):700#        self._write("(")701#        self._dispatch(t.left)702#        self._write(")" + self.binop[t.op.__class__.__name__] + "(")703#        self._dispatch(t.right)704#        self._write(")")705#706#    boolops = {_ast.And: 'and', _ast.Or: 'or'}707#    def _BoolOp(self, t):708#        self._write("(")709#        self._dispatch(t.values[0])710#        for v in t.values[1:]:711#            self._write(" %s " % self.boolops[t.op.__class__])712#            self._dispatch(v)713#        self._write(")")714#715#    def _Attribute(self,t):716#        self._dispatch(t.value)717#        self._write(".")718#        self._write(t.attr)719#720##    def _Call(self, t):721##        self._dispatch(t.func)722##        self._write("(")723##        comma = False724##        for e in t.args:725##            if comma: self._write(", ")726##            else: comma = True727##            self._dispatch(e)728##        for e in t.keywords:729##            if comma: self._write(", ")730##            else: comma = True731##            self._dispatch(e)732##        if t.starargs:733##            if comma: self._write(", ")734##            else: comma = True735##            self._write("*")736##            self._dispatch(t.starargs)737##        if t.kwargs:738##            if comma: self._write(", ")739##            else: comma = True740##            self._write("**")741##            self._dispatch(t.kwargs)742##        self._write(")")743#744#    # slice745#    def _Index(self, t):746#        self._dispatch(t.value)747#748#    def _ExtSlice(self, t):749#        for i, d in enumerate(t.dims):750#            if i != 0:751#                self._write(': ')752#            self._dispatch(d)753#754#    # others755#    def _arguments(self, t):756#        first = True757#        nonDef = len(t.args)-len(t.defaults)758#        for a in t.args[0:nonDef]:759#            if first:first = False760#            else: self._write(", ")761#            self._dispatch(a)762#        for a,d in zip(t.args[nonDef:], t.defaults):763#            if first:first = False764#            else: self._write(", ")765#            self._dispatch(a),766#            self._write("=")767#            self._dispatch(d)768#        if t.vararg:769#            if first:first = False770#            else: self._write(", ")771#            self._write("*"+t.vararg)772#        if t.kwarg:773#            if first:first = False774#            else: self._write(", ")775#            self._write("**"+t.kwarg)776#777##    def _keyword(self, t):778##        self._write(t.arg)779##        self._write("=")780##        self._dispatch(t.value)781#782#    def _Lambda(self, t):783#        self._write("lambda ")784#        self._dispatch(t.args)785#        self._write(": ")...