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fixes #146, JS globals were not understood by the renamer
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there are two basic strategies to fix: we either provide globals to the renamer, or it determines them based on use. I went with the second approach, as it fits more naturally with the current code generator.

[email protected]

Review URL: https://codereview.chromium.org/1099813006
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John Messerly committed Apr 22, 2015
1 parent 0efa91a commit 36518b8
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Showing 4 changed files with 128 additions and 64 deletions.
6 changes: 3 additions & 3 deletions pkg/dev_compiler/lib/runtime/dart/collection.js
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Original file line number Diff line number Diff line change
Expand Up @@ -2859,7 +2859,7 @@ var collection;
let _TypeTest = _TypeTest$();
let _comparator = Symbol('_comparator');
let _validKey = Symbol('_validKey');
let _internal = Symbol('_internal');
let _internal$ = Symbol('_internal');
let SplayTreeMap$ = dart.generic(function(K, V) {
class SplayTreeMap extends _SplayTree$(K) {
SplayTreeMap(compare, isValidKey) {
Expand Down Expand Up @@ -2903,7 +2903,7 @@ var collection;
[_compare](key1, key2) {
return this[_comparator](key1, key2);
}
[_internal]() {
[_internal$]() {
this[_comparator] = null;
this[_validKey] = null;
super._SplayTree();
Expand Down Expand Up @@ -3064,7 +3064,7 @@ var collection;
dart.defineNamedConstructor(SplayTreeMap, 'from');
dart.defineNamedConstructor(SplayTreeMap, 'fromIterable');
dart.defineNamedConstructor(SplayTreeMap, 'fromIterables');
dart.defineNamedConstructor(SplayTreeMap, _internal);
dart.defineNamedConstructor(SplayTreeMap, _internal$);
return SplayTreeMap;
});
let SplayTreeMap = SplayTreeMap$();
Expand Down
22 changes: 11 additions & 11 deletions pkg/dev_compiler/lib/runtime/dart/core.js
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Original file line number Diff line number Diff line change
Expand Up @@ -100,7 +100,7 @@ var core;
return Comparable;
});
let Comparable = Comparable$();
let _internal = dart.JsSymbol('_internal');
let _internal$ = dart.JsSymbol('_internal');
let _now = dart.JsSymbol('_now');
let _brokenDownDateToMillisecondsSinceEpoch = dart.JsSymbol('_brokenDownDateToMillisecondsSinceEpoch');
let _MAX_MILLISECONDS_SINCE_EPOCH = dart.JsSymbol('_MAX_MILLISECONDS_SINCE_EPOCH');
Expand All @@ -122,7 +122,7 @@ var core;
second = 0;
if (millisecond === void 0)
millisecond = 0;
this[_internal](year, month, day, hour, minute, second, millisecond, false);
this[_internal$](year, month, day, hour, minute, second, millisecond, false);
}
utc(year, month, day, hour, minute, second, millisecond) {
if (month === void 0)
Expand All @@ -137,7 +137,7 @@ var core;
second = 0;
if (millisecond === void 0)
millisecond = 0;
this[_internal](year, month, day, hour, minute, second, millisecond, true);
this[_internal$](year, month, day, hour, minute, second, millisecond, true);
}
now() {
this[_now]();
Expand Down Expand Up @@ -306,7 +306,7 @@ var core;
let otherMs = other.millisecondsSinceEpoch;
return new Duration({milliseconds: dart.notNull(ms) - dart.notNull(otherMs)});
}
[_internal](year, month, day, hour, minute, second, millisecond, isUtc) {
[_internal$](year, month, day, hour, minute, second, millisecond, isUtc) {
this.isUtc = typeof isUtc == 'boolean' ? isUtc : dart.throw_(new ArgumentError(isUtc));
this.millisecondsSinceEpoch = dart.as(_js_helper.checkInt(_js_helper.Primitives.valueFromDecomposedDate(year, month, day, hour, minute, second, millisecond, isUtc)), int);
}
Expand Down Expand Up @@ -356,7 +356,7 @@ var core;
dart.defineNamedConstructor(DateTime, 'utc');
dart.defineNamedConstructor(DateTime, 'now');
dart.defineNamedConstructor(DateTime, 'fromMillisecondsSinceEpoch');
dart.defineNamedConstructor(DateTime, _internal);
dart.defineNamedConstructor(DateTime, _internal$);
dart.defineNamedConstructor(DateTime, _now);
DateTime.MONDAY = 1;
DateTime.TUESDAY = 2;
Expand Down Expand Up @@ -1965,12 +1965,12 @@ var core;
} else if (char == Uri[_NUMBER_SIGN]) {
fragment = Uri[_makeFragment](uri, dart.notNull(index) + 1, uri.length);
}
return new Uri[_internal](scheme, userinfo, host, port, path, query, fragment);
return new Uri[_internal$](scheme, userinfo, host, port, path, query, fragment);
}
static [_fail](uri, index, message) {
throw new FormatException(message, uri, index);
}
[_internal](scheme, userInfo, host, port, path, query, fragment) {
[_internal$](scheme, userInfo, host, port, path, query, fragment) {
this.scheme = scheme;
this[_userInfo] = userInfo;
this[_host] = host;
Expand Down Expand Up @@ -2005,7 +2005,7 @@ var core;
}
let ensureLeadingSlash = host != null;
path = Uri[_makePath](path, 0, Uri[_stringOrNullLength](path), pathSegments, ensureLeadingSlash, isFile);
return new Uri[_internal](scheme, userInfo, host, port, path, query, fragment);
return new Uri[_internal$](scheme, userInfo, host, port, path, query, fragment);
}
http(authority, unencodedPath, queryParameters) {
if (queryParameters === void 0)
Expand Down Expand Up @@ -2215,7 +2215,7 @@ var core;
} else if (this.hasFragment) {
fragment = this.fragment;
}
return new Uri[_internal](scheme, userInfo, host, port, path, query, fragment);
return new Uri[_internal$](scheme, userInfo, host, port, path, query, fragment);
}
get pathSegments() {
if (this[_pathSegments] == null) {
Expand Down Expand Up @@ -2649,7 +2649,7 @@ var core;
}
}
let fragment = reference.hasFragment ? reference.fragment : null;
return new Uri[_internal](targetScheme, targetUserInfo, targetHost, targetPort, targetPath, targetQuery, fragment);
return new Uri[_internal$](targetScheme, targetUserInfo, targetHost, targetPort, targetPath, targetQuery, fragment);
}
get hasAuthority() {
return this[_host] != null;
Expand Down Expand Up @@ -3009,7 +3009,7 @@ var core;
return dart.notNull(codeUnit) >= dart.notNull(Uri[_LOWER_CASE_A]) && dart.notNull(codeUnit) <= dart.notNull(Uri[_LOWER_CASE_Z]) || dart.notNull(codeUnit) >= dart.notNull(Uri[_UPPER_CASE_A]) && dart.notNull(codeUnit) <= dart.notNull(Uri[_UPPER_CASE_Z]);
}
}
dart.defineNamedConstructor(Uri, _internal);
dart.defineNamedConstructor(Uri, _internal$);
dart.defineNamedConstructor(Uri, 'http');
dart.defineNamedConstructor(Uri, 'https');
dart.defineNamedConstructor(Uri, 'file');
Expand Down
127 changes: 77 additions & 50 deletions pkg/dev_compiler/lib/src/codegen/js_names.dart
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Original file line number Diff line number Diff line change
Expand Up @@ -34,7 +34,7 @@ class JSNamer extends LocalNamer {
JSNamer(Node node) : renames = new _RenameVisitor.build(node).renames;

String getName(Identifier node) {
var rename = renames[renameKey(node)];
var rename = renames[identifierKey(node)];
if (rename != null) return rename;

assert(!needsRename(node));
Expand All @@ -45,81 +45,108 @@ class JSNamer extends LocalNamer {
void leaveScope() {}
}

/// Represents a complete function scope in JS.
///
/// We don't currently track ES6 block scopes, because we don't represent them
/// in js_ast yet.
class _FunctionScope {
/// The parent scope.
final _FunctionScope parent;
final names = new HashSet<String>();

/// All names declared in this scope.
final declared = new HashSet<Object>();

/// All names [declared] in this scope or its [parent]s, that is used in this
/// scope and/or children. This is exactly the set of variable names we must
/// not collide with inside this scope.
final used = new HashSet<String>();

/// Nested functions, these are visited after everything else so the names
/// they might need are in scope.
final functions = new List<FunctionExpression>();

_FunctionScope(this.parent);
}

/// Collects all names used in the visited tree.
class _RenameVisitor extends BaseVisitor {
class _RenameVisitor extends VariableDeclarationVisitor {
final pendingRenames = new Map<Object, Set<_FunctionScope>>();
final renames = new HashMap<Object, String>();

_FunctionScope scope = new _FunctionScope(null);
final _FunctionScope rootScope = new _FunctionScope(null);
_FunctionScope scope;

_RenameVisitor.build(Node root) {
scope = rootScope;
root.accept(this);
_finishFunctions();
_finishNames();
}

declare(Identifier node) {
var id = identifierKey(node);
scope.declared.add(id);
_markUsed(node, id, scope);
}

visitIdentifier(Identifier node) {
var id = identifierKey(node);

// Find where the node was declared.
var declScope = scope;
while (declScope != null && !declScope.declared.contains(id)) {
declScope = declScope.parent;
}
if (declScope == null) {
// Assume it comes from the global scope.
declScope = rootScope;
declScope.declared.add(id);
}
_markUsed(node, id, declScope);
}

_markUsed(Identifier node, Object id, _FunctionScope declScope) {
// If it needs rename, we can't add it to the used name set yet, instead we
// will record all scopes it is visible in.
Set<_FunctionScope> usedIn = null;
if (needsRename(node)) {
// We can't assign the name yet, but we can add it to the list of things
// that need a name.
var id = renameKey(node);
pendingRenames.putIfAbsent(id, () => new HashSet()).add(scope);
} else {
scope.names.add(node.name);
usedIn = pendingRenames.putIfAbsent(id, () => new HashSet());
}

for (var s = scope, end = declScope.parent; s != end; s = s.parent) {
if (usedIn != null) {
usedIn.add(s);
} else {
s.used.add(node.name);
}
}
}

visitFunctionExpression(FunctionExpression node) {
scope = new _FunctionScope(scope);
super.visitFunctionExpression(node);
scope = scope.parent;
// Visit nested functions after all identifiers are declared.
scope.functions.add(node);
}

void _finishFunctions() {
for (var f in scope.functions) {
scope = new _FunctionScope(scope);
super.visitFunctionExpression(f);
_finishFunctions();
scope = scope.parent;
}
}

void _finishNames() {
var allNames = new Set<String>();
pendingRenames.forEach((id, scopes) {
var name = _findName(id, _allNamesInScope(scopes));
renames[id] = name;
for (var s in scopes) s.names.add(name);
});
}
allNames.clear();
for (var s in scopes) allNames.addAll(s.used);

// Given a set of scopes, populates [allNames] to include all names in those
// scopes as well as intermediate scopes. Returns the common parent of
// all scopes. For example:
//
// function outer(t) {
// function middle(x) {
// function inner() { return t; }
// foo(x);
// }
// }
//
// Here `t` is used in `inner` and `outer` but we need to include `middle`
// as well, so we know the rename of `t` to `x` is not valid.
static Set<String> _allNamesInScope(Set<_FunctionScope> scopes) {
// As we iterate, we'll add more scopes. We don't need to consider these
// as intermediate scopes can't introduce new intermediates.
var candidates = [];
var allScopes = scopes.toSet();
for (var scope in scopes) {
for (var p = scope.parent; p != null; p = p.parent) {
if (allScopes.contains(p)) {
allScopes.addAll(candidates);
break;
}
candidates.add(p);
}
// Discard these, we already added them or we didn't find a parent scope.
candidates.clear();
}
var name = _findName(id, allNames);
renames[id] = name;

// Now collect all names found.
return allScopes.expand((s) => s.names).toSet();
for (var s in scopes) s.used.add(name);
});
}

static String _findName(Object id, Set<String> usedNames) {
Expand Down Expand Up @@ -154,7 +181,7 @@ class _RenameVisitor extends BaseVisitor {
bool needsRename(Identifier node) =>
node is JSTemporary || node.allowRename && invalidJSVariableName(node.name);

Object /*String|JSTemporary*/ renameKey(Identifier node) =>
Object /*String|JSTemporary*/ identifierKey(Identifier node) =>
node is JSTemporary ? node : node.name;

/// Returns true for invalid JS variable names, such as keywords.
Expand Down
37 changes: 37 additions & 0 deletions pkg/dev_compiler/lib/src/js/printer.dart
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Original file line number Diff line number Diff line change
Expand Up @@ -1385,3 +1385,40 @@ class MinifyRenamer implements LocalNamer {
return newName;
}
}

/// Like [BaseVisitor], but calls [declare] for [Identifier] declarations, and
/// [visitIdentifier] otherwise.
abstract class VariableDeclarationVisitor<T> extends BaseVisitor<T> {
declare(Identifier node);

visitFunctionExpression(FunctionExpression node) {
for (Identifier param in node.params) declare(param);
node.body.accept(this);
}

visitVariableInitialization(VariableInitialization node) {
declare(node.declaration);
if (node.value != null) node.value.accept(this);
}

visitCatch(Catch node) {
declare(node.declaration);
node.body.accept(this);
}

visitFunctionDeclaration(FunctionDeclaration node) {
declare(node.name);
node.function.accept(this);
}

visitNamedFunction(NamedFunction node) {
declare(node.name);
node.function.accept(this);
}

visitClassExpression(ClassExpression node) {
declare(node.name);
if (node.heritage != null) node.heritage.accept(this);
for (Method element in node.methods) element.accept(this);
}
}

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