Fix null object conversion error in AST node #380
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In escodegen.js, converting a null object into source code in AST will generate an error on toString(). This is because the original judgment considers that the null object node has a "value" key value.
Previous code：escodegen.js-----Lines 2310 to 2313：
if (expr.value === null) {return 'null'; }
I think I can change the above code to:
if (expr.raw === 'null' && expr.value===undefined) {return 'null'; }
This way it can be converted from the ast tree to the original code when it encounters a null object normally.
testcase code(Nodejs environment):
var esprima=require("esprima");
var escodegen=require("escodegen");
var ast=esprima.parse("var a=null;");
var code=escodegen.generate(ast);
In escodegen.js, converting a null object into source code in AST will generate an error on toString(). This is because the original judgment considers that the null object node has a "value" key value.
Previous code：escodegen.js-----Lines 2310 to 2313：
if (expr.value === null || expr.raw === 'null' && expr.value===undefined) {return 'null'; }
I think I can change the above code to:
if (expr.raw === 'null' && expr.value===undefined) {return 'null'; }
This way it can be converted from the ast tree to the original code when it encounters a null object normally.
testcase code(Nodejs environment):
var esprima=require("esprima");
var escodegen=require("escodegen");
var ast=esprima.parse("var a=null;");
var code=escodegen.generate(ast);
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In escodegen.js, converting a null object into source code in AST will generate an error on toString(). This is because the original judgment considers that the null object node has a "value" key value.
Previous code：escodegen.js-----Lines 2310 to 2313：
if (expr.value === null) {return 'null'; }
I think I can change the above code to:
if (expr.value === null || (expr.raw === 'null' && expr.value===undefined)) {return 'null'; }
This way it can be converted from the ast tree to the original code when it encounters a null object normally.
testcase code(Nodejs environment):
var esprima=require("esprima");
var escodegen=require("escodegen");
var ast=esprima.parse("var a=null;");
var code=escodegen.generate(ast);