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authorFlorian Dold <florian.dold@gmail.com>2017-05-03 15:35:00 +0200
committerFlorian Dold <florian.dold@gmail.com>2017-05-03 15:35:00 +0200
commitde98e0b232509d5f40c135d540a70e415272ff85 (patch)
treea79222a5b58484ab3b80d18efcaaa7ccc4769b33 /node_modules/acorn/src/parseutil.js
parente0c9d480a73fa629c1e4a47d3e721f1d2d345406 (diff)
node_modules
Diffstat (limited to 'node_modules/acorn/src/parseutil.js')
-rw-r--r--node_modules/acorn/src/parseutil.js128
1 files changed, 128 insertions, 0 deletions
diff --git a/node_modules/acorn/src/parseutil.js b/node_modules/acorn/src/parseutil.js
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+++ b/node_modules/acorn/src/parseutil.js
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+import {types as tt} from "./tokentype"
+import {Parser} from "./state"
+import {lineBreak, skipWhiteSpace} from "./whitespace"
+
+const pp = Parser.prototype
+
+// ## Parser utilities
+
+const literal = /^(?:'((?:[^']|\.)*)'|"((?:[^"]|\.)*)"|;)/
+pp.strictDirective = function(start) {
+ for (;;) {
+ skipWhiteSpace.lastIndex = start
+ start += skipWhiteSpace.exec(this.input)[0].length
+ let match = literal.exec(this.input.slice(start))
+ if (!match) return false
+ if ((match[1] || match[2]) == "use strict") return true
+ start += match[0].length
+ }
+}
+
+// Predicate that tests whether the next token is of the given
+// type, and if yes, consumes it as a side effect.
+
+pp.eat = function(type) {
+ if (this.type === type) {
+ this.next()
+ return true
+ } else {
+ return false
+ }
+}
+
+// Tests whether parsed token is a contextual keyword.
+
+pp.isContextual = function(name) {
+ return this.type === tt.name && this.value === name
+}
+
+// Consumes contextual keyword if possible.
+
+pp.eatContextual = function(name) {
+ return this.value === name && this.eat(tt.name)
+}
+
+// Asserts that following token is given contextual keyword.
+
+pp.expectContextual = function(name) {
+ if (!this.eatContextual(name)) this.unexpected()
+}
+
+// Test whether a semicolon can be inserted at the current position.
+
+pp.canInsertSemicolon = function() {
+ return this.type === tt.eof ||
+ this.type === tt.braceR ||
+ lineBreak.test(this.input.slice(this.lastTokEnd, this.start))
+}
+
+pp.insertSemicolon = function() {
+ if (this.canInsertSemicolon()) {
+ if (this.options.onInsertedSemicolon)
+ this.options.onInsertedSemicolon(this.lastTokEnd, this.lastTokEndLoc)
+ return true
+ }
+}
+
+// Consume a semicolon, or, failing that, see if we are allowed to
+// pretend that there is a semicolon at this position.
+
+pp.semicolon = function() {
+ if (!this.eat(tt.semi) && !this.insertSemicolon()) this.unexpected()
+}
+
+pp.afterTrailingComma = function(tokType, notNext) {
+ if (this.type == tokType) {
+ if (this.options.onTrailingComma)
+ this.options.onTrailingComma(this.lastTokStart, this.lastTokStartLoc)
+ if (!notNext)
+ this.next()
+ return true
+ }
+}
+
+// Expect a token of a given type. If found, consume it, otherwise,
+// raise an unexpected token error.
+
+pp.expect = function(type) {
+ this.eat(type) || this.unexpected()
+}
+
+// Raise an unexpected token error.
+
+pp.unexpected = function(pos) {
+ this.raise(pos != null ? pos : this.start, "Unexpected token")
+}
+
+export class DestructuringErrors {
+ constructor() {
+ this.shorthandAssign = this.trailingComma = this.parenthesizedAssign = this.parenthesizedBind = -1
+ }
+}
+
+pp.checkPatternErrors = function(refDestructuringErrors, isAssign) {
+ if (!refDestructuringErrors) return
+ if (refDestructuringErrors.trailingComma > -1)
+ this.raiseRecoverable(refDestructuringErrors.trailingComma, "Comma is not permitted after the rest element")
+ let parens = isAssign ? refDestructuringErrors.parenthesizedAssign : refDestructuringErrors.parenthesizedBind
+ if (parens > -1) this.raiseRecoverable(parens, "Parenthesized pattern")
+}
+
+pp.checkExpressionErrors = function(refDestructuringErrors, andThrow) {
+ let pos = refDestructuringErrors ? refDestructuringErrors.shorthandAssign : -1
+ if (!andThrow) return pos >= 0
+ if (pos > -1) this.raise(pos, "Shorthand property assignments are valid only in destructuring patterns")
+}
+
+pp.checkYieldAwaitInDefaultParams = function() {
+ if (this.yieldPos && (!this.awaitPos || this.yieldPos < this.awaitPos))
+ this.raise(this.yieldPos, "Yield expression cannot be a default value")
+ if (this.awaitPos)
+ this.raise(this.awaitPos, "Await expression cannot be a default value")
+}
+
+pp.isSimpleAssignTarget = function(expr) {
+ if (expr.type === "ParenthesizedExpression")
+ return this.isSimpleAssignTarget(expr.expression)
+ return expr.type === "Identifier" || expr.type === "MemberExpression"
+}