getJSDocHost always returns a defined result (microsoft#24255)

Andy · web-flow · commit 7f0258bcb987 · 2018-05-18T13:20:13.000-07:00
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -2172,8 +2172,7 @@ namespace ts {
                 return;
             }
             const host = getJSDocHost(node);
-            if (host &&
-                isExpressionStatement(host) &&
+            if (isExpressionStatement(host) &&
                 isBinaryExpression(host.expression) &&
                 getSpecialPropertyAssignmentKind(host.expression) === SpecialPropertyAssignmentKind.PrototypeProperty) {
                 const symbol = getSymbolOfNode(host.expression.left);
diff --git a/src/compiler/utilities.ts b/src/compiler/utilities.ts
@@ -1927,11 +1927,7 @@ namespace ts {
     }
 
     export function getJSDocHost(node: Node): HasJSDoc {
-        const comment = findAncestor(node.parent,
-            node => !(isJSDocNode(node) || node.flags & NodeFlags.JSDoc) ? "quit" : node.kind === SyntaxKind.JSDocComment);
-        if (comment) {
-            return (comment as JSDoc).parent;
-        }
+        return Debug.assertDefined(findAncestor(node.parent, isJSDoc)).parent;
     }
 
     export function getTypeParameterFromJsDoc(node: TypeParameterDeclaration & { parent: JSDocTemplateTag }): TypeParameterDeclaration | undefined {

Original file line number	Diff line number	Diff line change
`@@ -1927,11 +1927,7 @@ namespace ts {`
`1927`	`1927`	`}`
`1928`	`1928`
`1929`	`1929`	`export function getJSDocHost(node: Node): HasJSDoc {`
`1930`		`- const comment = findAncestor(node.parent,`
`1931`		`- node => !(isJSDocNode(node) \|\| node.flags & NodeFlags.JSDoc) ? "quit" : node.kind === SyntaxKind.JSDocComment);`
`1932`		`- if (comment) {`
`1933`		`- return (comment as JSDoc).parent;`
`1934`		`- }`
	`1930`	`+ return Debug.assertDefined(findAncestor(node.parent, isJSDoc)).parent;`
`1935`	`1931`	`}`
`1936`	`1932`
`1937`	`1933`	`export function getTypeParameterFromJsDoc(node: TypeParameterDeclaration & { parent: JSDocTemplateTag }): TypeParameterDeclaration \| undefined {`