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instrumenter.js
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instrumenter.js
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/*
Copyright (c) 2012, Yahoo! Inc. All rights reserved.
Copyrights licensed under the New BSD License. See the accompanying LICENSE file for terms.
*/
/*global esprima, escodegen, window */
(function (isNode) {
"use strict";
var SYNTAX,
nodeType,
ESP = isNode ? require('esprima') : esprima,
ESPGEN = isNode ? require('escodegen') : escodegen, //TODO - package as dependency
crypto = isNode ? require('crypto') : null,
LEADER_WRAP = '(function () { ',
TRAILER_WRAP = '\n}());',
COMMENT_RE = /^\s*istanbul\s+ignore\s+(if|else|next)(?=\W|$)/,
astgen,
preconditions,
cond,
isArray = Array.isArray;
/* istanbul ignore if: untestable */
if (!isArray) {
isArray = function (thing) { return thing && Object.prototype.toString.call(thing) === '[object Array]'; };
}
if (!isNode) {
preconditions = {
'Could not find esprima': ESP,
'Could not find escodegen': ESPGEN,
'JSON object not in scope': JSON,
'Array does not implement push': [].push,
'Array does not implement unshift': [].unshift
};
/* istanbul ignore next: untestable */
for (cond in preconditions) {
if (preconditions.hasOwnProperty(cond)) {
if (!preconditions[cond]) { throw new Error(cond); }
}
}
}
function generateTrackerVar(filename, omitSuffix) {
var hash, suffix;
if (crypto !== null) {
hash = crypto.createHash('md5');
hash.update(filename);
suffix = hash.digest('base64');
//trim trailing equal signs, turn identifier unsafe chars to safe ones + => _ and / => $
suffix = suffix.replace(new RegExp('=', 'g'), '')
.replace(new RegExp('\\+', 'g'), '_')
.replace(new RegExp('/', 'g'), '$');
} else {
window.__cov_seq = window.__cov_seq || 0;
window.__cov_seq += 1;
suffix = window.__cov_seq;
}
return '__cov_' + (omitSuffix ? '' : suffix);
}
function pushAll(ary, thing) {
if (!isArray(thing)) {
thing = [ thing ];
}
Array.prototype.push.apply(ary, thing);
}
SYNTAX = {
// keep in sync with estraverse's VisitorKeys
AssignmentExpression: ['left', 'right'],
AssignmentPattern: ['left', 'right'],
ArrayExpression: ['elements'],
ArrayPattern: ['elements'],
ArrowFunctionExpression: ['params', 'body'],
AwaitExpression: ['argument'], // CAUTION: It's deferred to ES7.
BlockStatement: ['body'],
BinaryExpression: ['left', 'right'],
BreakStatement: ['label'],
CallExpression: ['callee', 'arguments'],
CatchClause: ['param', 'body'],
ClassBody: ['body'],
ClassDeclaration: ['id', 'superClass', 'body'],
ClassExpression: ['id', 'superClass', 'body'],
ComprehensionBlock: ['left', 'right'], // CAUTION: It's deferred to ES7.
ComprehensionExpression: ['blocks', 'filter', 'body'], // CAUTION: It's deferred to ES7.
ConditionalExpression: ['test', 'consequent', 'alternate'],
ContinueStatement: ['label'],
DebuggerStatement: [],
DirectiveStatement: [],
DoWhileStatement: ['body', 'test'],
EmptyStatement: [],
ExportAllDeclaration: ['source'],
ExportDefaultDeclaration: ['declaration'],
ExportNamedDeclaration: ['declaration', 'specifiers', 'source'],
ExportSpecifier: ['exported', 'local'],
ExpressionStatement: ['expression'],
ForStatement: ['init', 'test', 'update', 'body'],
ForInStatement: ['left', 'right', 'body'],
ForOfStatement: ['left', 'right', 'body'],
FunctionDeclaration: ['id', 'params', 'body'],
FunctionExpression: ['id', 'params', 'body'],
GeneratorExpression: ['blocks', 'filter', 'body'], // CAUTION: It's deferred to ES7.
Identifier: [],
IfStatement: ['test', 'consequent', 'alternate'],
ImportDeclaration: ['specifiers', 'source'],
ImportDefaultSpecifier: ['local'],
ImportNamespaceSpecifier: ['local'],
ImportSpecifier: ['imported', 'local'],
Literal: [],
LabeledStatement: ['label', 'body'],
LogicalExpression: ['left', 'right'],
MetaProperty: ['meta', 'property'],
MemberExpression: ['object', 'property'],
MethodDefinition: ['key', 'value'],
ModuleSpecifier: [],
NewExpression: ['callee', 'arguments'],
ObjectExpression: ['properties'],
ObjectPattern: ['properties'],
Program: ['body'],
Property: ['key', 'value'],
RestElement: [ 'argument' ],
ReturnStatement: ['argument'],
SequenceExpression: ['expressions'],
SpreadElement: ['argument'],
Super: [],
SwitchStatement: ['discriminant', 'cases'],
SwitchCase: ['test', 'consequent'],
TaggedTemplateExpression: ['tag', 'quasi'],
TemplateElement: [],
TemplateLiteral: ['quasis', 'expressions'],
ThisExpression: [],
ThrowStatement: ['argument'],
TryStatement: ['block', 'handler', 'finalizer'],
UnaryExpression: ['argument'],
UpdateExpression: ['argument'],
VariableDeclaration: ['declarations'],
VariableDeclarator: ['id', 'init'],
WhileStatement: ['test', 'body'],
WithStatement: ['object', 'body'],
YieldExpression: ['argument']
};
for (nodeType in SYNTAX) {
/* istanbul ignore else: has own property */
if (SYNTAX.hasOwnProperty(nodeType)) {
SYNTAX[nodeType] = { name: nodeType, children: SYNTAX[nodeType] };
}
}
astgen = {
variable: function (name) { return { type: SYNTAX.Identifier.name, name: name }; },
stringLiteral: function (str) { return { type: SYNTAX.Literal.name, value: String(str) }; },
numericLiteral: function (num) { return { type: SYNTAX.Literal.name, value: Number(num) }; },
statement: function (contents) { return { type: SYNTAX.ExpressionStatement.name, expression: contents }; },
dot: function (obj, field) { return { type: SYNTAX.MemberExpression.name, computed: false, object: obj, property: field }; },
subscript: function (obj, sub) { return { type: SYNTAX.MemberExpression.name, computed: true, object: obj, property: sub }; },
postIncrement: function (obj) { return { type: SYNTAX.UpdateExpression.name, operator: '++', prefix: false, argument: obj }; },
sequence: function (one, two) { return { type: SYNTAX.SequenceExpression.name, expressions: [one, two] }; },
returnStatement: function (expr) { return { type: SYNTAX.ReturnStatement.name, argument: expr }; }
};
function Walker(walkMap, preprocessor, scope, debug) {
this.walkMap = walkMap;
this.preprocessor = preprocessor;
this.scope = scope;
this.debug = debug;
if (this.debug) {
this.level = 0;
this.seq = true;
}
}
function defaultWalker(node, walker) {
var type = node.type,
preprocessor,
postprocessor,
children = SYNTAX[type],
// don't run generated nodes thru custom walks otherwise we will attempt to instrument the instrumentation code :)
applyCustomWalker = !!node.loc || node.type === SYNTAX.Program.name,
walkerFn = applyCustomWalker ? walker.walkMap[type] : null,
i,
j,
walkFnIndex,
childType,
childNode,
ret,
childArray,
childElement,
pathElement,
assignNode,
isLast;
if (!SYNTAX[type]) {
console.error(node);
console.error('Unsupported node type:' + type);
return;
}
children = SYNTAX[type].children;
/* istanbul ignore if: guard */
if (node.walking) { throw new Error('Infinite regress: Custom walkers may NOT call walker.apply(node)'); }
node.walking = true;
ret = walker.apply(node, walker.preprocessor);
preprocessor = ret.preprocessor;
if (preprocessor) {
delete ret.preprocessor;
ret = walker.apply(node, preprocessor);
}
if (isArray(walkerFn)) {
for (walkFnIndex = 0; walkFnIndex < walkerFn.length; walkFnIndex += 1) {
isLast = walkFnIndex === walkerFn.length - 1;
ret = walker.apply(ret, walkerFn[walkFnIndex]);
/*istanbul ignore next: paranoid check */
if (ret.type !== type && !isLast) {
throw new Error('Only the last walker is allowed to change the node type: [type was: ' + type + ' ]');
}
}
} else {
if (walkerFn) {
ret = walker.apply(node, walkerFn);
}
}
if (node.skipSelf) {
return;
}
for (i = 0; i < children.length; i += 1) {
childType = children[i];
childNode = node[childType];
if (childNode && !childNode.skipWalk) {
pathElement = { node: node, property: childType };
if (isArray(childNode)) {
childArray = [];
for (j = 0; j < childNode.length; j += 1) {
childElement = childNode[j];
pathElement.index = j;
if (childElement) {
assignNode = walker.apply(childElement, null, pathElement);
if (isArray(assignNode.prepend)) {
pushAll(childArray, assignNode.prepend);
delete assignNode.prepend;
}
} else {
assignNode = undefined;
}
pushAll(childArray, assignNode);
}
node[childType] = childArray;
} else {
assignNode = walker.apply(childNode, null, pathElement);
/*istanbul ignore if: paranoid check */
if (isArray(assignNode.prepend)) {
throw new Error('Internal error: attempt to prepend statements in disallowed (non-array) context');
/* if this should be allowed, this is how to solve it
tmpNode = { type: 'BlockStatement', body: [] };
pushAll(tmpNode.body, assignNode.prepend);
pushAll(tmpNode.body, assignNode);
node[childType] = tmpNode;
delete assignNode.prepend;
*/
} else {
node[childType] = assignNode;
}
}
}
}
postprocessor = ret.postprocessor;
if (postprocessor) {
delete ret.postprocessor;
ret = walker.apply(ret, postprocessor);
}
delete node.walking;
return ret;
}
Walker.prototype = {
startWalk: function (node) {
this.path = [];
this.apply(node);
},
apply: function (node, walkFn, pathElement) {
var ret, i, seq, prefix;
walkFn = walkFn || defaultWalker;
if (this.debug) {
this.seq += 1;
this.level += 1;
seq = this.seq;
prefix = '';
for (i = 0; i < this.level; i += 1) { prefix += ' '; }
console.log(prefix + 'Enter (' + seq + '):' + node.type);
}
if (pathElement) { this.path.push(pathElement); }
ret = walkFn.call(this.scope, node, this);
if (pathElement) { this.path.pop(); }
if (this.debug) {
this.level -= 1;
console.log(prefix + 'Return (' + seq + '):' + node.type);
}
return ret || node;
},
startLineForNode: function (node) {
return node && node.loc && node.loc.start ? node.loc.start.line : /* istanbul ignore next: guard */ null;
},
ancestor: function (n) {
return this.path.length > n - 1 ? this.path[this.path.length - n] : /* istanbul ignore next: guard */ null;
},
parent: function () {
return this.ancestor(1);
},
isLabeled: function () {
var el = this.parent();
return el && el.node.type === SYNTAX.LabeledStatement.name;
}
};
/**
* mechanism to instrument code for coverage. It uses the `esprima` and
* `escodegen` libraries for JS parsing and code generation respectively.
*
* Works on `node` as well as the browser.
*
* Usage on nodejs
* ---------------
*
* var instrumenter = new require('istanbul').Instrumenter(),
* changed = instrumenter.instrumentSync('function meaningOfLife() { return 42; }', 'filename.js');
*
* Usage in a browser
* ------------------
*
* Load `esprima.js`, `escodegen.js` and `instrumenter.js` (this file) using `script` tags or other means.
*
* Create an instrumenter object as:
*
* var instrumenter = new Instrumenter(),
* changed = instrumenter.instrumentSync('function meaningOfLife() { return 42; }', 'filename.js');
*
* Aside from demonstration purposes, it is unclear why you would want to instrument code in a browser.
*
* @class Instrumenter
* @constructor
* @param {Object} options Optional. Configuration options.
* @param {String} [options.coverageVariable] the global variable name to use for
* tracking coverage. Defaults to `__coverage__`
* @param {Boolean} [options.embedSource] whether to embed the source code of every
* file as an array in the file coverage object for that file. Defaults to `false`
* @param {Boolean} [options.preserveComments] whether comments should be preserved in the output. Defaults to `false`
* @param {Boolean} [options.noCompact] emit readable code when set. Defaults to `false`
* @param {Boolean} [options.esModules] whether the code to instrument contains uses es
* imports or exports.
* @param {Boolean} [options.noAutoWrap] do not automatically wrap the source in
* an anonymous function before covering it. By default, code is wrapped in
* an anonymous function before it is parsed. This is done because
* some nodejs libraries have `return` statements outside of
* a function which is technically invalid Javascript and causes the parser to fail.
* This construct, however, works correctly in node since module loading
* is done in the context of an anonymous function.
*
* Note that the semantics of the code *returned* by the instrumenter does not change in any way.
* The function wrapper is "unwrapped" before the instrumented code is generated.
* @param {Object} [options.codeGenerationOptions] an object that is directly passed to the `escodegen`
* library as configuration for code generation. The `noCompact` setting is not honored when this
* option is specified
* @param {Boolean} [options.debug] assist in debugging. Currently, the only effect of
* setting this option is a pretty-print of the coverage variable. Defaults to `false`
* @param {Boolean} [options.walkDebug] assist in debugging of the AST walker used by this class.
*
*/
function Instrumenter(options) {
this.opts = options || {
debug: false,
walkDebug: false,
coverageVariable: '__coverage__',
codeGenerationOptions: undefined,
noAutoWrap: false,
noCompact: false,
embedSource: false,
preserveComments: false,
esModules: false
};
if (this.opts.esModules && !this.opts.noAutoWrap) {
this.opts.noAutoWrap = true;
if (this.opts.debug) {
console.log('Setting noAutoWrap to true as required by esModules');
}
}
this.walker = new Walker({
ArrowFunctionExpression: [ this.arrowBlockConverter ],
ExpressionStatement: this.coverStatement,
ExportNamedDeclaration: this.coverExport,
BreakStatement: this.coverStatement,
ContinueStatement: this.coverStatement,
DebuggerStatement: this.coverStatement,
ReturnStatement: this.coverStatement,
ThrowStatement: this.coverStatement,
TryStatement: [ this.paranoidHandlerCheck, this.coverStatement],
VariableDeclaration: this.coverStatement,
IfStatement: [ this.ifBlockConverter, this.coverStatement, this.ifBranchInjector ],
ForStatement: [ this.skipInit, this.loopBlockConverter, this.coverStatement ],
ForInStatement: [ this.skipLeft, this.loopBlockConverter, this.coverStatement ],
ForOfStatement: [ this.skipLeft, this.loopBlockConverter, this.coverStatement ],
WhileStatement: [ this.loopBlockConverter, this.coverStatement ],
DoWhileStatement: [ this.loopBlockConverter, this.coverStatement ],
SwitchStatement: [ this.coverStatement, this.switchBranchInjector ],
SwitchCase: [ this.switchCaseInjector ],
WithStatement: [ this.withBlockConverter, this.coverStatement ],
FunctionDeclaration: [ this.coverFunction, this.coverStatement ],
FunctionExpression: this.coverFunction,
LabeledStatement: this.coverStatement,
ConditionalExpression: this.conditionalBranchInjector,
LogicalExpression: this.logicalExpressionBranchInjector,
ObjectExpression: this.maybeAddType,
MetaProperty: this.coverMetaProperty,
}, this.extractCurrentHint, this, this.opts.walkDebug);
//unit testing purposes only
if (this.opts.backdoor && this.opts.backdoor.omitTrackerSuffix) {
this.omitTrackerSuffix = true;
}
}
Instrumenter.prototype = {
/**
* synchronous instrumentation method. Throws when illegal code is passed to it
* @method instrumentSync
* @param {String} code the code to be instrumented as a String
* @param {String} filename Optional. The name of the file from which
* the code was read. A temporary filename is generated when not specified.
* Not specifying a filename is only useful for unit tests and demonstrations
* of this library.
*/
instrumentSync: function (code, filename) {
var program;
//protect from users accidentally passing in a Buffer object instead
if (typeof code !== 'string') { throw new Error('Code must be string'); }
if (code.charAt(0) === '#') { //shebang, 'comment' it out, won't affect syntax tree locations for things we care about
code = '//' + code;
}
if (!this.opts.noAutoWrap) {
code = LEADER_WRAP + code + TRAILER_WRAP;
}
try {
program = ESP.parse(code, {
loc: true,
range: true,
tokens: this.opts.preserveComments,
comment: true,
sourceType: this.opts.esModules ? 'module' : 'script'
});
} catch (e) {
console.log('Failed to parse file: ' + filename);
throw e;
}
if (this.opts.preserveComments) {
program = ESPGEN.attachComments(program, program.comments, program.tokens);
}
if (!this.opts.noAutoWrap) {
program = {
type: SYNTAX.Program.name,
body: program.body[0].expression.callee.body.body,
comments: program.comments
};
}
return this.instrumentASTSync(program, filename, code);
},
filterHints: function (comments) {
var ret = [],
i,
comment,
groups;
if (!(comments && isArray(comments))) {
return ret;
}
for (i = 0; i < comments.length; i += 1) {
comment = comments[i];
/* istanbul ignore else: paranoid check */
if (comment && comment.value && comment.range && isArray(comment.range)) {
groups = String(comment.value).match(COMMENT_RE);
if (groups) {
ret.push({ type: groups[1], start: comment.range[0], end: comment.range[1] });
}
}
}
return ret;
},
extractCurrentHint: function (node) {
if (!node.range) { return; }
var i = this.currentState.lastHintPosition + 1,
hints = this.currentState.hints,
nodeStart = node.range[0],
hint;
this.currentState.currentHint = null;
while (i < hints.length) {
hint = hints[i];
if (hint.end < nodeStart) {
this.currentState.currentHint = hint;
this.currentState.lastHintPosition = i;
i += 1;
} else {
break;
}
}
},
/**
* synchronous instrumentation method that instruments an AST instead.
* @method instrumentASTSync
* @param {String} program the AST to be instrumented
* @param {String} filename Optional. The name of the file from which
* the code was read. A temporary filename is generated when not specified.
* Not specifying a filename is only useful for unit tests and demonstrations
* of this library.
* @param {String} originalCode the original code corresponding to the AST,
* used for embedding the source into the coverage object
*/
instrumentASTSync: function (program, filename, originalCode) {
var usingStrict = false,
codegenOptions,
generated,
preamble,
lineCount,
i;
filename = filename || String(new Date().getTime()) + '.js';
this.sourceMap = null;
this.coverState = {
path: filename,
s: {},
b: {},
f: {},
fnMap: {},
statementMap: {},
branchMap: {}
};
this.currentState = {
trackerVar: generateTrackerVar(filename, this.omitTrackerSuffix),
func: 0,
branch: 0,
variable: 0,
statement: 0,
hints: this.filterHints(program.comments),
currentHint: null,
lastHintPosition: -1,
ignoring: 0
};
if (program.body && program.body.length > 0 && this.isUseStrictExpression(program.body[0])) {
//nuke it
program.body.shift();
//and add it back at code generation time
usingStrict = true;
}
this.walker.startWalk(program);
codegenOptions = this.opts.codeGenerationOptions || { format: { compact: !this.opts.noCompact }};
codegenOptions.comment = this.opts.preserveComments;
//console.log(JSON.stringify(program, undefined, 2));
generated = ESPGEN.generate(program, codegenOptions);
preamble = this.getPreamble(originalCode || '', usingStrict);
if (generated.map && generated.code) {
lineCount = preamble.split(/\r\n|\r|\n/).length;
// offset all the generated line numbers by the number of lines in the preamble
for (i = 0; i < generated.map._mappings._array.length; i += 1) {
generated.map._mappings._array[i].generatedLine += lineCount;
}
this.sourceMap = generated.map;
generated = generated.code;
}
return preamble + '\n' + generated + '\n';
},
/**
* Callback based instrumentation. Note that this still executes synchronously in the same process tick
* and calls back immediately. It only provides the options for callback style error handling as
* opposed to a `try-catch` style and nothing more. Implemented as a wrapper over `instrumentSync`
*
* @method instrument
* @param {String} code the code to be instrumented as a String
* @param {String} filename Optional. The name of the file from which
* the code was read. A temporary filename is generated when not specified.
* Not specifying a filename is only useful for unit tests and demonstrations
* of this library.
* @param {Function(err, instrumentedCode)} callback - the callback function
*/
instrument: function (code, filename, callback) {
if (!callback && typeof filename === 'function') {
callback = filename;
filename = null;
}
try {
callback(null, this.instrumentSync(code, filename));
} catch (ex) {
callback(ex);
}
},
/**
* returns the file coverage object for the code that was instrumented
* just before calling this method. Note that this represents a
* "zero-coverage" object which is not even representative of the code
* being loaded in node or a browser (which would increase the statement
* counts for mainline code).
* @method lastFileCoverage
* @return {Object} a "zero-coverage" file coverage object for the code last instrumented
* by this instrumenter
*/
lastFileCoverage: function () {
return this.coverState;
},
/**
* returns the source map object for the code that was instrumented
* just before calling this method.
* @method lastSourceMap
* @return {Object} a source map object for the code last instrumented
* by this instrumenter
*/
lastSourceMap: function () {
return this.sourceMap;
},
fixColumnPositions: function (coverState) {
var offset = LEADER_WRAP.length,
fixer = function (loc) {
if (loc.start.line === 1) {
loc.start.column -= offset;
}
if (loc.end.line === 1) {
loc.end.column -= offset;
}
},
k,
obj,
i,
locations;
obj = coverState.statementMap;
for (k in obj) {
/* istanbul ignore else: has own property */
if (obj.hasOwnProperty(k)) { fixer(obj[k]); }
}
obj = coverState.fnMap;
for (k in obj) {
/* istanbul ignore else: has own property */
if (obj.hasOwnProperty(k)) { fixer(obj[k].loc); }
}
obj = coverState.branchMap;
for (k in obj) {
/* istanbul ignore else: has own property */
if (obj.hasOwnProperty(k)) {
locations = obj[k].locations;
for (i = 0; i < locations.length; i += 1) {
fixer(locations[i]);
}
}
}
},
getPreamble: function (sourceCode, emitUseStrict) {
var varName = this.opts.coverageVariable || '__coverage__',
file = this.coverState.path.replace(/\\/g, '\\\\'),
tracker = this.currentState.trackerVar,
coverState,
strictLine = emitUseStrict ? '"use strict";' : '',
// return replacements using the function to ensure that the replacement is
// treated like a dumb string and not as a string with RE replacement patterns
replacer = function (s) {
return function () { return s; };
},
code;
if (!this.opts.noAutoWrap) {
this.fixColumnPositions(this.coverState);
}
if (this.opts.embedSource) {
this.coverState.code = sourceCode.split(/(?:\r?\n)|\r/);
}
coverState = this.opts.debug ? JSON.stringify(this.coverState, undefined, 4) : JSON.stringify(this.coverState);
code = [
"%STRICT%",
"var %VAR% = (Function('return this'))();",
"if (!%VAR%.%GLOBAL%) { %VAR%.%GLOBAL% = {}; }",
"%VAR% = %VAR%.%GLOBAL%;",
"if (!(%VAR%['%FILE%'])) {",
" %VAR%['%FILE%'] = %OBJECT%;",
"}",
"%VAR% = %VAR%['%FILE%'];"
].join("\n")
.replace(/%STRICT%/g, replacer(strictLine))
.replace(/%VAR%/g, replacer(tracker))
.replace(/%GLOBAL%/g, replacer(varName))
.replace(/%FILE%/g, replacer(file))
.replace(/%OBJECT%/g, replacer(coverState));
return code;
},
startIgnore: function () {
this.currentState.ignoring += 1;
},
endIgnore: function () {
this.currentState.ignoring -= 1;
},
convertToBlock: function (node) {
if (!node) {
return { type: 'BlockStatement', body: [] };
} else if (node.type === 'BlockStatement') {
return node;
} else {
return { type: 'BlockStatement', body: [ node ] };
}
},
arrowBlockConverter: function (node) {
var retStatement;
if (node.expression) { // turn expression nodes into a block with a return statement
retStatement = astgen.returnStatement(node.body);
// ensure the generated return statement is covered
retStatement.loc = node.body.loc;
node.body = this.convertToBlock(retStatement);
node.expression = false;
}
},
paranoidHandlerCheck: function (node) {
// if someone is using an older esprima on the browser
// convert handlers array to single handler attribute
// containing its first element
/* istanbul ignore next */
if (!node.handler && node.handlers) {
node.handler = node.handlers[0];
}
},
ifBlockConverter: function (node) {
node.consequent = this.convertToBlock(node.consequent);
node.alternate = this.convertToBlock(node.alternate);
},
loopBlockConverter: function (node) {
node.body = this.convertToBlock(node.body);
},
withBlockConverter: function (node) {
node.body = this.convertToBlock(node.body);
},
statementName: function (location, initValue) {
var sName,
ignoring = !!this.currentState.ignoring;
location.skip = ignoring || undefined;
initValue = initValue || 0;
this.currentState.statement += 1;
sName = this.currentState.statement;
this.coverState.statementMap[sName] = location;
this.coverState.s[sName] = initValue;
return sName;
},
skipInit: function (node /*, walker */) {
if (node.init) {
node.init.skipWalk = true;
}
},
skipLeft: function (node /*, walker */) {
node.left.skipWalk = true;
},
isUseStrictExpression: function (node) {
return node && node.type === SYNTAX.ExpressionStatement.name &&
node.expression && node.expression.type === SYNTAX.Literal.name &&
node.expression.value === 'use strict';
},
maybeSkipNode: function (node, type) {
var alreadyIgnoring = !!this.currentState.ignoring,
hint = this.currentState.currentHint,
ignoreThis = !alreadyIgnoring && hint && hint.type === type;
if (ignoreThis) {
this.startIgnore();
node.postprocessor = this.endIgnore;
return true;
}
return false;
},
coverMetaProperty: function(node /* , walker */) {
node.skipSelf = true;
},
coverStatement: function (node, walker) {
var sName,
incrStatementCount,
parent,
grandParent;
this.maybeSkipNode(node, 'next');
if (this.isUseStrictExpression(node)) {
grandParent = walker.ancestor(2);
/* istanbul ignore else: difficult to test */
if (grandParent) {
if ((grandParent.node.type === SYNTAX.FunctionExpression.name ||
grandParent.node.type === SYNTAX.FunctionDeclaration.name) &&
walker.parent().node.body[0] === node) {
return;
}
}
}
if (node.type === SYNTAX.FunctionDeclaration.name) {
// Called for the side-effect of setting the function's statement count to 1.
this.statementName(node.loc, 1);
} else {
// We let `coverExport` handle ExportNamedDeclarations.
parent = walker.parent();
if (parent && parent.node.type === SYNTAX.ExportNamedDeclaration.name) {
return;
}
sName = this.statementName(node.loc);
incrStatementCount = astgen.statement(
astgen.postIncrement(
astgen.subscript(
astgen.dot(astgen.variable(this.currentState.trackerVar), astgen.variable('s')),
astgen.stringLiteral(sName)
)
)
);
this.splice(incrStatementCount, node, walker);
}
},
coverExport: function (node, walker) {
var sName, incrStatementCount;
if ( !node.declaration || !node.declaration.declarations ) { return; }
this.maybeSkipNode(node, 'next');
sName = this.statementName(node.declaration.loc);
incrStatementCount = astgen.statement(
astgen.postIncrement(
astgen.subscript(
astgen.dot(astgen.variable(this.currentState.trackerVar), astgen.variable('s')),
astgen.stringLiteral(sName)
)
)
);
this.splice(incrStatementCount, node, walker);
},
splice: function (statements, node, walker) {
var targetNode = walker.isLabeled() ? walker.parent().node : node;
targetNode.prepend = targetNode.prepend || [];
pushAll(targetNode.prepend, statements);
},
functionName: function (node, line, location) {
this.currentState.func += 1;
var id = this.currentState.func,
ignoring = !!this.currentState.ignoring,
name = node.id ? node.id.name : '(anonymous_' + id + ')',
clone = function (attr) {
var obj = location[attr] || /* istanbul ignore next */ {};
return { line: obj.line, column: obj.column };
};
this.coverState.fnMap[id] = {
name: name, line: line,
loc: {
start: clone('start'),
end: clone('end')
},
skip: ignoring || undefined
};
this.coverState.f[id] = 0;
return id;
},
coverFunction: function (node, walker) {
var id,
body = node.body,
blockBody = body.body,
popped;
this.maybeSkipNode(node, 'next');
id = this.functionName(node, walker.startLineForNode(node), {
start: node.loc.start,
end: { line: node.body.loc.start.line, column: node.body.loc.start.column }
});
if (blockBody.length > 0 && this.isUseStrictExpression(blockBody[0])) {
popped = blockBody.shift();
}
blockBody.unshift(
astgen.statement(
astgen.postIncrement(
astgen.subscript(
astgen.dot(astgen.variable(this.currentState.trackerVar), astgen.variable('f')),
astgen.stringLiteral(id)
)
)
)
);
if (popped) {
blockBody.unshift(popped);
}
},
branchName: function (type, startLine, pathLocations) {
var bName,
paths = [],
locations = [],
i,
ignoring = !!this.currentState.ignoring;
this.currentState.branch += 1;
bName = this.currentState.branch;
for (i = 0; i < pathLocations.length; i += 1) {
pathLocations[i].skip = pathLocations[i].skip || ignoring || undefined;
locations.push(pathLocations[i]);
paths.push(0);
}
this.coverState.b[bName] = paths;
this.coverState.branchMap[bName] = { line: startLine, type: type, locations: locations };
return bName;
},
branchIncrementExprAst: function (varName, branchIndex, down) {
var ret = astgen.postIncrement(
astgen.subscript(
astgen.subscript(
astgen.dot(astgen.variable(this.currentState.trackerVar), astgen.variable('b')),
astgen.stringLiteral(varName)
),
astgen.numericLiteral(branchIndex)
),
down
);
return ret;
},
locationsForNodes: function (nodes) {
var ret = [],
i;
for (i = 0; i < nodes.length; i += 1) {
ret.push(nodes[i].loc);
}
return ret;
},
ifBranchInjector: function (node, walker) {
var alreadyIgnoring = !!this.currentState.ignoring,
hint = this.currentState.currentHint,
ignoreThen = !alreadyIgnoring && hint && hint.type === 'if',
ignoreElse = !alreadyIgnoring && hint && hint.type === 'else',
line = node.loc.start.line,
col = node.loc.start.column,
makeLoc = function () { return { line: line, column: col }; },
bName = this.branchName('if', walker.startLineForNode(node), [
{ start: makeLoc(), end: makeLoc(), skip: ignoreThen || undefined },
{ start: makeLoc(), end: makeLoc(), skip: ignoreElse || undefined }
]),
thenBody = node.consequent.body,
elseBody = node.alternate.body,
child;
thenBody.unshift(astgen.statement(this.branchIncrementExprAst(bName, 0)));
elseBody.unshift(astgen.statement(this.branchIncrementExprAst(bName, 1)));
if (ignoreThen) { child = node.consequent; child.preprocessor = this.startIgnore; child.postprocessor = this.endIgnore; }
if (ignoreElse) { child = node.alternate; child.preprocessor = this.startIgnore; child.postprocessor = this.endIgnore; }
},
branchLocationFor: function (name, index) {
return this.coverState.branchMap[name].locations[index];
},
switchBranchInjector: function (node, walker) {
var cases = node.cases,
bName,
i;
if (!(cases && cases.length > 0)) {