Skip to content

Commit

Permalink
Update dynamic imports AST
Browse files Browse the repository at this point in the history
  • Loading branch information
@mysticatea @marijnh
mysticatea authored and marijnh committed Aug 12, 2019
1 parent ac6decb commit 091933c
Show file tree
Hide file tree
Showing 3 changed files with 190 additions and 45 deletions.
21 changes: 16 additions & 5 deletions acorn-loose/src/expression.js
View file
Original file line number Diff line number Diff line change
Expand Up @@ -297,8 +297,8 @@ lp.parseExprAtom = function() {
return this.parseTemplate()

case tt._import:
if (this.options.ecmaVersion > 10) {
return this.parseDynamicImport()
if (this.options.ecmaVersion >= 11) {
return this.parseExprImport()
} else {
return this.dummyIdent()
}
Expand All @@ -308,10 +308,21 @@ lp.parseExprAtom = function() {
}
}

lp.parseDynamicImport = function() {
lp.parseExprImport = function() {
const node = this.startNode()
this.next()
return this.finishNode(node, "Import")
this.next() // skip `import`
switch (this.tok.type) {
case tt.parenL:
return this.parseDynamicImport(node)
default:
node.name = "import"
return this.finishNode(node, "Identifier")
}
}

lp.parseDynamicImport = function(node) {
node.source = this.parseExprList(tt.parenR)[0] || this.dummyString()
return this.finishNode(node, "ImportExpression")
}

lp.parseNew = function() {
Expand Down
53 changes: 32 additions & 21 deletions acorn/src/expression.js
View file
Original file line number Diff line number Diff line change
Expand Up @@ -281,7 +281,7 @@ pp.parseSubscript = function(base, startPos, startLoc, noCalls, maybeAsyncArrow)
this.yieldPos = 0
this.awaitPos = 0
this.awaitIdentPos = 0
let exprList = this.parseExprList(tt.parenR, this.options.ecmaVersion >= 8 && base.type !== "Import", false, refDestructuringErrors)
let exprList = this.parseExprList(tt.parenR, this.options.ecmaVersion >= 8, false, refDestructuringErrors)
if (maybeAsyncArrow && !this.canInsertSemicolon() && this.eat(tt.arrow)) {
this.checkPatternErrors(refDestructuringErrors, false)
this.checkYieldAwaitInDefaultParams()
Expand All @@ -299,16 +299,6 @@ pp.parseSubscript = function(base, startPos, startLoc, noCalls, maybeAsyncArrow)
let node = this.startNodeAt(startPos, startLoc)
node.callee = base
node.arguments = exprList
if (node.callee.type === "Import") {
if (node.arguments.length !== 1) {
this.raise(node.start, "import() requires exactly one argument")
}

const importArg = node.arguments[0]
if (importArg && importArg.type === "SpreadElement") {
this.raise(importArg.start, "... is not allowed in import()")
}
}
base = this.finishNode(node, "CallExpression")
} else if (this.type === tt.backQuote) {
let node = this.startNodeAt(startPos, startLoc)
Expand Down Expand Up @@ -420,8 +410,8 @@ pp.parseExprAtom = function(refDestructuringErrors) {
return this.parseTemplate()

case tt._import:
if (this.options.ecmaVersion > 10) {
return this.parseDynamicImport()
if (this.options.ecmaVersion >= 11) {
return this.parseExprImport()
} else {
return this.unexpected()
}
Expand All @@ -431,13 +421,34 @@ pp.parseExprAtom = function(refDestructuringErrors) {
}
}

pp.parseDynamicImport = function() {
pp.parseExprImport = function() {
const node = this.startNode()
this.next()
if (this.type !== tt.parenL) {
this.next() // skip `import`
switch (this.type) {
case tt.parenL:
return this.parseDynamicImport(node)
default:
this.unexpected()
}
return this.finishNode(node, "Import")
}

pp.parseDynamicImport = function(node) {
this.next() // skip `(`

// Parse node.source.
node.source = this.parseMaybeAssign()

// Verify ending.
if (!this.eat(tt.parenR)) {
const errorPos = this.start
if (this.eat(tt.comma) && this.eat(tt.parenR)) {
this.raiseRecoverable(errorPos, "Trailing comma is not allowed in import()")
} else {
this.unexpected(errorPos)
}
}

return this.finishNode(node, "ImportExpression")
}

pp.parseLiteral = function(value) {
Expand Down Expand Up @@ -547,12 +558,12 @@ pp.parseNew = function() {
this.raiseRecoverable(node.start, "new.target can only be used in functions")
return this.finishNode(node, "MetaProperty")
}
let startPos = this.start, startLoc = this.startLoc
let startPos = this.start, startLoc = this.startLoc, isImport = this.type === tt._import
node.callee = this.parseSubscripts(this.parseExprAtom(), startPos, startLoc, true)
if (this.options.ecmaVersion > 10 && node.callee.type === "Import") {
this.raise(node.callee.start, "Cannot use new with import(...)")
if (isImport && node.callee.type === "ImportExpression") {
this.raise(startPos, "Cannot use new with import()")
}
if (this.eat(tt.parenL)) node.arguments = this.parseExprList(tt.parenR, this.options.ecmaVersion >= 8 && node.callee.type !== "Import", false)
if (this.eat(tt.parenL)) node.arguments = this.parseExprList(tt.parenR, this.options.ecmaVersion >= 8, false)
else node.arguments = empty
return this.finishNode(node, "NewExpression")
}
Expand Down
161 changes: 142 additions & 19 deletions test/tests-dynamic-import.js
View file
Original file line number Diff line number Diff line change
Expand Up @@ -17,19 +17,16 @@ test(
start: 0,
end: 26,
expression: {
type: 'CallExpression',
type: 'ImportExpression',
start: 0,
end: 26,
callee: { type: 'Import', start: 0, end: 6 },
arguments: [
{
type: 'Literal',
start: 7,
end: 25,
value: 'dynamicImport.js',
raw: "'dynamicImport.js'"
}
]
source: {
type: 'Literal',
start: 7,
end: 25,
value: 'dynamicImport.js',
raw: "'dynamicImport.js'"
}
}
}
],
Expand All @@ -38,6 +35,49 @@ test(
{ ecmaVersion: 11 }
);

// Assignment is OK.
test(
"import(a = 'dynamicImport.js')",
{
"type": "Program",
"start": 0,
"end": 30,
"body": [
{
"type": "ExpressionStatement",
"start": 0,
"end": 30,
"expression": {
"type": "ImportExpression",
"start": 0,
"end": 30,
"source": {
"type": "AssignmentExpression",
"start": 7,
"end": 29,
"operator": "=",
"left": {
"type": "Identifier",
"start": 7,
"end": 8,
"name": "a"
},
"right": {
"type": "Literal",
"start": 11,
"end": 29,
"value": "dynamicImport.js",
"raw": "'dynamicImport.js'"
}
}
}
}
],
"sourceType": "script"
},
{ ecmaVersion: 11 }
);

test(
"function* a() { yield import('http'); }",
{
Expand Down Expand Up @@ -69,11 +109,10 @@ test(
end: 36,
delegate: false,
argument: {
type: 'CallExpression',
type: 'ImportExpression',
start: 22,
end: 36,
callee: { type: 'Import', start: 22, end: 28 },
arguments: [{ type: 'Literal', start: 29, end: 35, value: 'http', raw: "'http'" }]
source: { type: 'Literal', start: 29, end: 35, value: 'http', raw: "'http'" }
}
}
}
Expand All @@ -86,6 +125,85 @@ test(
{ ecmaVersion: 11 }
);

// `new import(s)` is syntax error, but `new (import(s))` is not.
test(
"new (import(s))",
{
"type": "Program",
"start": 0,
"end": 15,
"body": [
{
"type": "ExpressionStatement",
"start": 0,
"end": 15,
"expression": {
"type": "NewExpression",
"start": 0,
"end": 15,
"callee": {
"type": "ImportExpression",
"start": 5,
"end": 14,
"source": {
"type": "Identifier",
"start": 12,
"end": 13,
"name": "s"
}
},
"arguments": []
}
}
],
"sourceType": "script"
},
{ ecmaVersion: 11 }
);

// `import(s,t)` is syntax error, but `import((s,t))` is not.
test(
"import((s,t))",
{
"type": "Program",
"start": 0,
"end": 13,
"body": [
{
"type": "ExpressionStatement",
"start": 0,
"end": 13,
"expression": {
"type": "ImportExpression",
"start": 0,
"end": 13,
"source": {
"type": "SequenceExpression",
"start": 8,
"end": 11,
"expressions": [
{
"type": "Identifier",
"start": 8,
"end": 9,
"name": "s"
},
{
"type": "Identifier",
"start": 10,
"end": 11,
"name": "t"
}
]
}
}
}
],
"sourceType": "script"
},
{ ecmaVersion: 11 }
);

testFail('function failsParse() { return import.then(); }', 'Unexpected token (1:37)', {
ecmaVersion: 11,
loose: false
Expand All @@ -102,27 +220,32 @@ testFail("import('test.js')", 'Unexpected token (1:6)', {
sourceType: 'module'
});

testFail("import()", 'import() requires exactly one argument (1:0)', {
testFail("import()", 'Unexpected token (1:7)', {
ecmaVersion: 11,
loose: false
});

testFail("import(a, b)", 'Unexpected token (1:8)', {
ecmaVersion: 11,
loose: false
});

testFail("import(a, b)", 'import() requires exactly one argument (1:0)', {
testFail("import(...[a])", 'Unexpected token (1:7)', {
ecmaVersion: 11,
loose: false
});

testFail("import(...[a])", '... is not allowed in import() (1:7)', {
testFail("import(source,)", 'Trailing comma is not allowed in import() (1:13)', {
ecmaVersion: 11,
loose: false
});

testFail("import(source,)", 'Unexpected token (1:14)', {
testFail("new import(source)", 'Cannot use new with import() (1:4)', {
ecmaVersion: 11,
loose: false
});

testFail("new import(source)", 'Cannot use new with import(...) (1:4)', {
testFail("(import)(s)", 'Unexpected token (1:7)', {
ecmaVersion: 11,
loose: false
});

0 comments on commit 091933c

Please sign in to comment.