Merge pull request #1079 from Microsoft/showNarrowedType

Show narrowed type in quickInfo/completion entry

Author: sheetalkamat

src/compiler/checker.ts

@@ -85,7 +85,7 @@ module ts {
             checkProgram: checkProgram,
             emitFiles: invokeEmitter,
             getParentOfSymbol: getParentOfSymbol,
-            getTypeOfSymbol: getTypeOfSymbol,
+            getNarrowedTypeOfSymbol: getNarrowedTypeOfSymbol,
             getDeclaredTypeOfSymbol: getDeclaredTypeOfSymbol,
             getPropertiesOfType: getPropertiesOfType,
             getPropertyOfType: getPropertyOfType,

src/compiler/types.ts

@@ -701,7 +701,7 @@ module ts {
         checkProgram(): void;
         emitFiles(targetSourceFile?: SourceFile): EmitResult;
         getParentOfSymbol(symbol: Symbol): Symbol;
-        getTypeOfSymbol(symbol: Symbol): Type;
+        getNarrowedTypeOfSymbol(symbol: Symbol, node: Node): Type;
         getDeclaredTypeOfSymbol(symbol: Symbol): Type;
         getPropertiesOfType(type: Type): Symbol[];
         getPropertyOfType(type: Type, propertyName: string): Symbol;

src/services/services.ts

@@ -2689,14 +2689,13 @@ module ts {
 
             var symbol = lookUp(activeCompletionSession.symbols, entryName);
             if (symbol) {
-                var type = session.typeChecker.getTypeOfSymbol(symbol);
-                Debug.assert(type !== undefined, "Could not find type for symbol");
                 var completionEntry = createCompletionEntry(symbol, session.typeChecker);
                 // TODO(drosen): Right now we just permit *all* semantic meanings when calling 'getSymbolKind'
                 //               which is permissible given that it is backwards compatible; but really we should consider
                 //               passing the meaning for the node so that we don't report that a suggestion for a value is an interface.
                 //               We COULD also just do what 'getSymbolModifiers' does, which is to use the first declaration.
                 var location = getTouchingPropertyName(sourceFile, position);
+                Debug.assert(session.typeChecker.getNarrowedTypeOfSymbol(symbol, location) !== undefined, "Could not find type for symbol");
                 var displayPartsDocumentationsAndSymbolKind = getSymbolDisplayPartsDocumentationAndSymbolKind(symbol, getSourceFile(filename), location, session.typeChecker, location, SemanticMeaning.All);
                 return {
                     name: entryName,
@@ -2868,7 +2867,7 @@ module ts {
                     symbolKind = ScriptElementKind.memberVariableElement;
                 }
 
-                var type = typeResolver.getTypeOfSymbol(symbol);
+                var type = typeResolver.getNarrowedTypeOfSymbol(symbol, location);
                 if (type) {
                     if (location.parent && location.parent.kind === SyntaxKind.PropertyAccess) {
                         var right = (<PropertyAccess>location.parent).right;

tests/cases/fourslash/completionEntryOnNarrowedType.ts

@@ -0,0 +1,20 @@
+/// <reference path='fourslash.ts'/>
+
+////function foo(strOrNum: string | number) {
+////    /*1*/
+////    if (typeof strOrNum === "number") {
+////        /*2*/ 
+////    }
+////    else {
+////        /*3*/
+////    }
+////}
+
+goTo.marker('1');
+verify.completionListContains("strOrNum", "(parameter) strOrNum: string | number");
+
+goTo.marker('2');
+verify.completionListContains("strOrNum", "(parameter) strOrNum: number");
+
+goTo.marker('3');
+verify.completionListContains("strOrNum", "(parameter) strOrNum: string");

tests/cases/fourslash/quickInfoOnNarrowedType.ts

@@ -0,0 +1,22 @@
+/// <reference path='fourslash.ts'/>
+
+////function foo(strOrNum: string | number) {
+////    if (typeof /*1*/strOrNum === "number") {
+////        return /*2*/strOrNum; 
+////    }
+////    else {
+////        return /*3*/strOrNum.length;
+////    }
+////}
+
+goTo.marker('1');
+verify.quickInfoIs('(parameter) strOrNum: string | number');
+verify.completionListContains("strOrNum", "(parameter) strOrNum: string | number");
+
+goTo.marker('2');
+verify.quickInfoIs('(parameter) strOrNum: number');
+verify.completionListContains("strOrNum", "(parameter) strOrNum: number");
+
+goTo.marker('3');
+verify.quickInfoIs('(parameter) strOrNum: string');
+verify.completionListContains("strOrNum", "(parameter) strOrNum: string");

tests/cases/fourslash/quickInfoOnNarrowedTypeInModule.ts

@@ -0,0 +1,51 @@
+/// <reference path='fourslash.ts'/>
+
+////var strOrNum: string | number;
+////module m {
+////    var nonExportedStrOrNum: string | number;
+////    export var exportedStrOrNum: string | number;
+////    var num: number;
+////    var str: string;
+////    if (typeof /*1*/nonExportedStrOrNum === "number") {
+////        num = /*2*/nonExportedStrOrNum; 
+////    }
+////    else {
+////        str = /*3*/nonExportedStrOrNum.length;
+////    }
+////    if (typeof /*4*/exportedStrOrNum === "number") {
+////        strOrNum = /*5*/exportedStrOrNum;
+////    }
+////    else {
+////        strOrNum = /*6*/exportedStrOrNum;
+////    }
+////}
+////if (typeof m./*7*/exportedStrOrNum === "number") {
+////    strOrNum = m./*8*/exportedStrOrNum;
+////}
+////else {
+////    strOrNum = m./*9*/exportedStrOrNum;
+////}
+
+goTo.marker('1');
+verify.quickInfoIs('(var) nonExportedStrOrNum: string | number');
+verify.completionListContains("nonExportedStrOrNum", "(var) nonExportedStrOrNum: string | number");
+
+goTo.marker('2');
+verify.quickInfoIs('(var) nonExportedStrOrNum: number');
+verify.completionListContains("nonExportedStrOrNum", "(var) nonExportedStrOrNum: number");
+
+goTo.marker('3');
+verify.quickInfoIs('(var) nonExportedStrOrNum: string');
+verify.completionListContains("nonExportedStrOrNum", "(var) nonExportedStrOrNum: string");
+
+['4', '5', '6', '7', '8', '9'].forEach((marker, index, arr) => {
+    goTo.marker(marker);
+    verify.quickInfoIs('(var) m.exportedStrOrNum: string | number');
+    verify.completionListContains("exportedStrOrNum", "(var) m.exportedStrOrNum: string | number");
+});
+
+['7', '8', '9'].forEach((marker, index, arr) => {
+    goTo.marker(marker);
+    verify.quickInfoIs('(var) m.exportedStrOrNum: string | number');
+    verify.memberListContains("exportedStrOrNum", "(var) m.exportedStrOrNum: string | number");
+});