feat(utils): add parse_type() (#21)

ikatyang · Aug 2, 2017 · ae0192f · ae0192f
1 parent b61a3e0
commit ae0192f
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Showing 3 changed files with 93 additions and 1 deletion.
diff --git a/src/__tests__/__snapshots__/parse.ts.snap b/src/__tests__/__snapshots__/parse.ts.snap
@@ -1,5 +1,78 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`parse_type should return correctly 1`] = `
+Object {
+  "generics": Array [
+    Object {
+      "defalut": undefined,
+      "extends": undefined,
+      "kind": 13,
+      "name": "T",
+    },
+    Object {
+      "defalut": undefined,
+      "extends": undefined,
+      "kind": 13,
+      "name": "U",
+    },
+  ],
+  "kind": 11,
+  "parameters": Array [
+    Object {
+      "kind": 32,
+      "name": "x",
+      "optional": undefined,
+      "rest": undefined,
+      "type": Object {
+        "generics": undefined,
+        "kind": 12,
+        "name": "T",
+        "parents": undefined,
+      },
+    },
+    Object {
+      "kind": 32,
+      "name": "y",
+      "optional": undefined,
+      "rest": undefined,
+      "type": Object {
+        "generics": undefined,
+        "kind": 12,
+        "name": "U",
+        "parents": undefined,
+      },
+    },
+  ],
+  "return": Object {
+    "kind": 41,
+    "types": Array [
+      Object {
+        "generics": undefined,
+        "kind": 12,
+        "name": "T",
+        "parents": undefined,
+      },
+      Object {
+        "generics": undefined,
+        "kind": 12,
+        "name": "U",
+        "parents": undefined,
+      },
+      Object {
+        "kind": 29,
+        "type": TokenObject {
+          "end": -1,
+          "flags": 8,
+          "kind": 105,
+          "parent": undefined,
+          "pos": -1,
+        },
+      },
+    ],
+  },
+}
+`;
+
 exports[`should return correctly 1`] = `
 "/// <reference path=\\"some-path\\" />
 /// <reference types=\\"some-types\\" />

diff --git a/src/__tests__/parse.ts b/src/__tests__/parse.ts
@@ -1,6 +1,6 @@
 import * as ts from 'typescript';
 import { emit } from '../emit';
-import { parse, parse_native } from '../parse';
+import { parse, parse_native, parse_type } from '../parse';
 
 const code = `
 /// <reference path="some-path" />
@@ -138,3 +138,13 @@ it('should return correctly', () => {
 it('should throw error with unexpected kind', () => {
   expect(() => parse_native(ts.createToken(-1))).toThrowError();
 });
+
+describe('parse_type', () => {
+  it('should return correctly', () => {
+    expect(
+      parse_type(`
+        <T, U>(x: T, y: U) => T | U | void
+      `),
+    ).toMatchSnapshot();
+  });
+});
diff --git a/src/parse.ts b/src/parse.ts
@@ -1,4 +1,5 @@
 import * as ts from 'typescript';
+import { IType } from './collections';
 import {
   any_type,
   boolean_type,
@@ -12,6 +13,7 @@ import {
   undefined_type,
   void_type,
 } from './constants';
+import { ITypeDeclaration } from './declarations/type-declaration';
 import { IElement } from './element';
 import { emit_native } from './emit';
 import { ITopLevelElement } from './others/top-level-element';
@@ -132,3 +134,10 @@ export const parse = (code: string) =>
       /*setParentNodes */ false,
     ),
   ) as ITopLevelElement;
+
+export const parse_type = (type_string: string) => {
+  const code = `type X = ${type_string}`;
+  const top_level_element = parse(code);
+  const type_declaration = top_level_element.members[0] as ITypeDeclaration;
+  return type_declaration.type!;
+};