maxmustermann/TypeScript
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

Address CR feedback + defer creation of visited map

Browse source
This commit is contained in:
Anders Hejlsberg 2017-05-16 09:12:32 -07:00
parent e9ccb16642
commit ed1a6c10e2
1 changed files with 21 additions and 32 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

53
src/compiler/checker.ts
View file

@ -10096,31 +10096,12 @@ namespace ts {
inferTypes(context.signature.typeParameters, context.inferences, originalSource, originalTarget);
}
function getSymbolForInference(type: Type) {
// Exclude the static side of classes since it shares its symbol with the instance side which leads
// to false positives.
return type.flags & TypeFlags.Object && !(getObjectFlags(type) & ObjectFlags.Anonymous && type.symbol && type.symbol.flags & SymbolFlags.Class) ? type.symbol : undefined;
}
function inferTypes(typeVariables: TypeVariable[], typeInferences: TypeInferences[], originalSource: Type, originalTarget: Type) {
let stack: Type[];
let depth = 0;
let symbolStack: Symbol[];
let visited: Map<boolean>;
let inferiority = 0;
const visited = createMap<boolean>();
inferFromTypes(originalSource, originalTarget);
function isInstantiationInProcess(type: Type) {
const symbol = getSymbolForInference(type);
if (symbol) {
for (let i = 0; i < depth; i++) {
const t = stack[i];
if (getSymbolForInference(t) === symbol) {
return true;
}
}
}
}
function inferFromTypes(source: Type, target: Type) {
if (!couldContainTypeVariables(target)) {
return;
@ -10248,21 +10229,29 @@ namespace ts {
else {
source = getApparentType(source);
if (source.flags & TypeFlags.Object) {
const key = source.id + "," + target.id;
if (visited && visited.get(key)) {
return;
}
(visited || (visited = createMap<boolean>())).set(key, true);
// If we are already processing another target type with the same associated symbol (such as
// an instantiation of the same generic type), we do not explore this target as it would yield
// no further inferences.
if (isInstantiationInProcess(target)) {
return;
// no further inferences. We exclude the static side of classes from this check since it shares
// its symbol with the instance side which would lead to false positives.
const isNonConstructorObject = target.flags & TypeFlags.Object &&
!(getObjectFlags(target) & ObjectFlags.Anonymous && target.symbol && target.symbol.flags & SymbolFlags.Class);
const symbol = isNonConstructorObject ? target.symbol : undefined;
if (symbol) {
if (contains(symbolStack, symbol)) {
return;
}
(symbolStack || (symbolStack = [])).push(symbol);
inferFromObjectTypes(source, target);
symbolStack.pop();
}
const key = source.id + "," + target.id;
if (visited.get(key)) {
return;
else {
inferFromObjectTypes(source, target);
}
visited.set(key, true);
(stack || (stack = []))[depth] = target;
depth++;
inferFromObjectTypes(source, target);
depth--;
}
}
}