Allow for aliased importing (#156)

Author: tommy-mitchell

source/lib/parser.ts

@@ -1,4 +1,4 @@
-import {Program, Node, CallExpression, forEachChild, isCallExpression, Identifier} from '@tsd/typescript';
+import {Program, Node, CallExpression, forEachChild, isCallExpression, isPropertyAccessExpression, SymbolFlags} from '@tsd/typescript';
 import {Assertion} from './assertions';
 import {Location, Diagnostic} from './interfaces';
 
@@ -11,13 +11,24 @@ const assertionFnNames = new Set<string>(Object.values(Assertion));
  */
 export const extractAssertions = (program: Program): Map<Assertion, Set<CallExpression>> => {
 	const assertions = new Map<Assertion, Set<CallExpression>>();
+	const checker = program.getTypeChecker();
 
 	/**
 	 * Recursively loop over all the nodes and extract all the assertions out of the source files.
 	 */
 	function walkNodes(node: Node) {
 		if (isCallExpression(node)) {
-			const identifier = (node.expression as Identifier).getText();
+			const expression = isPropertyAccessExpression(node.expression) ?
+				node.expression.name :
+				node.expression;
+
+			// eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+			const maybeAlias = checker.getSymbolAtLocation(expression)!;
+			const symbol = maybeAlias.flags & SymbolFlags.Alias ?
+				checker.getAliasedSymbol(maybeAlias) :
+				maybeAlias;
+
+			const identifier = symbol.getName();
 
 			// Check if the call type is a valid assertion
 			if (assertionFnNames.has(identifier)) {

source/test/fixtures/aliased/aliased-assertion/index.d.ts

@@ -0,0 +1,7 @@
+declare const one: {
+	(foo: string, bar: string): string;
+	(foo: number, bar: number): number;
+	<T extends string>(foo: T, bar: T): string;
+};
+
+export default one;

source/test/fixtures/aliased/aliased-assertion/index.js

@@ -0,0 +1 @@
+module.exports.default = (foo, bar) => foo + bar;

source/test/fixtures/aliased/aliased-assertion/index.test-d.ts

@@ -0,0 +1,4 @@
+import {expectType as et} from '../../../..';
+import one from '.';
+
+et<number>(one(1, 1));

source/test/fixtures/aliased/aliased-assertion/package.json

@@ -0,0 +1,3 @@
+{
+	"name": "foo"
+}

source/test/fixtures/aliased/aliased-const/index.d.ts

@@ -0,0 +1,7 @@
+declare const one: {
+	(foo: string, bar: string): string;
+	(foo: number, bar: number): number;
+	<T extends string>(foo: T, bar: T): string;
+};
+
+export default one;

source/test/fixtures/aliased/aliased-const/index.js

@@ -0,0 +1 @@
+module.exports.default = (foo, bar) => foo + bar;

source/test/fixtures/aliased/aliased-const/index.test-d.ts

@@ -0,0 +1,8 @@
+import * as tsd from '../../../..';
+import one from '.';
+
+const x = tsd;
+x.expectError(one(true, true));
+
+const y = {z: tsd};
+y.z.expectError(one(true, true));

source/test/fixtures/aliased/aliased-const/package.json

@@ -0,0 +1,3 @@
+{
+	"name": "foo"
+}

source/test/fixtures/aliased/aliased-module/index.d.ts

@@ -0,0 +1,7 @@
+declare const one: {
+	(foo: string, bar: string): string;
+	(foo: number, bar: number): number;
+	<T extends string>(foo: T, bar: T): string;
+};
+
+export default one;

source/test/fixtures/aliased/aliased-module/index.js

@@ -0,0 +1 @@
+module.exports.default = (foo, bar) => foo + bar;

source/test/fixtures/aliased/aliased-module/index.test-d.ts

@@ -0,0 +1,9 @@
+import * as tsd from '../../../..';
+import {expectType, expectError} from '../../../..';
+import one from '.';
+
+expectType<number>(one(1, 1));
+tsd.expectType<number>(one(1, 1));
+
+expectError(one(true, true));
+tsd.expectError(one(true, true));

source/test/fixtures/aliased/aliased-module/package.json

@@ -0,0 +1,3 @@
+{
+	"name": "foo"
+}

source/test/test.ts

@@ -455,3 +455,21 @@ test('prints the types of expressions passed to `printType` helper', async t =>
 		[10, 0, 'warning', 'Type for expression `\'foo\'` is: `"foo"`'],
 	]);
 });
+
+test('assertions should be identified if imported as an aliased module', async t => {
+	const diagnostics = await tsd({cwd: path.join(__dirname, 'fixtures/aliased/aliased-module')});
+
+	verify(t, diagnostics, []);
+});
+
+test('assertions should be identified if imported as an alias', async t => {
+	const diagnostics = await tsd({cwd: path.join(__dirname, 'fixtures/aliased/aliased-assertion')});
+
+	verify(t, diagnostics, []);
+});
+
+test('assertions should be identified if aliased', async t => {
+	const diagnostics = await tsd({cwd: path.join(__dirname, 'fixtures/aliased/aliased-const')});
+
+	verify(t, diagnostics, []);
+});