feat: #672 - Add Type#getPropertyOrThrow

dsherret · Sep 1, 2019 · c929c6c · c929c6c
1 parent 37476f8
commit c929c6c
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Showing 3 changed files with 76 additions and 10 deletions.
diff --git a/lib/ts-morph.d.ts b/lib/ts-morph.d.ts
@@ -10818,11 +10818,24 @@ export declare class Type<TType extends ts.Type = ts.Type> {
      */
     getProperties(): Symbol[];
     /**
-     * Gets a property.
+     * Gets a property or throws if it doesn't exist.
      * @param name - By a name.
+     */
+    getPropertyOrThrow(name: string): Symbol;
+    /**
+     * Gets a property or throws if it doesn't exist.
      * @param findFunction - Function for searching for a property.
      */
+    getPropertyOrThrow(findFunction: (declaration: Symbol) => boolean): Symbol;
+    /**
+     * Gets a property or returns undefined if it does not exist.
+     * @param name - By a name.
+     */
     getProperty(name: string): Symbol | undefined;
+    /**
+     * Gets a property or returns undefined if it does not exist.
+     * @param findFunction - Function for searching for a property.
+     */
     getProperty(findFunction: (declaration: Symbol) => boolean): Symbol | undefined;
     /**
      * Gets the apparent properties of the type.

diff --git a/src/compiler/types/Type.ts b/src/compiler/types/Type.ts
@@ -1,7 +1,7 @@
 import * as errors from "../../errors";
 import { ProjectContext } from "../../ProjectContext";
 import { ObjectFlags, ts, TypeFlags, TypeFormatFlags } from "../../typescript";
-import { getSymbolByNameOrFindFunction, TypeGuards } from "../../utils";
+import { getSymbolByNameOrFindFunction, TypeGuards, getNotFoundErrorMessageForNameOrFindFunction } from "../../utils";
 import { Signature, Symbol } from "../symbols";
 import { Node } from "../ast";
 import { TypeParameter } from "./TypeParameter";
@@ -153,12 +153,34 @@ export class Type<TType extends ts.Type = ts.Type> {
     }
 
     /**
-     * Gets a property.
+     * Gets a property or throws if it doesn't exist.
      * @param name - By a name.
+     */
+    getPropertyOrThrow(name: string): Symbol;
+    /**
+     * Gets a property or throws if it doesn't exist.
      * @param findFunction - Function for searching for a property.
      */
+    getPropertyOrThrow(findFunction: (declaration: Symbol) => boolean): Symbol;
+    /** @internal */
+    getPropertyOrThrow(nameOrFindFunction: string | ((declaration: Symbol) => boolean)): Symbol;
+    getPropertyOrThrow(nameOrFindFunction: string | ((declaration: Symbol) => boolean)): Symbol {
+        return errors.throwIfNullOrUndefined(this.getProperty(nameOrFindFunction),
+            () => getNotFoundErrorMessageForNameOrFindFunction("symbol property", nameOrFindFunction));
+    }
+
+    /**
+     * Gets a property or returns undefined if it does not exist.
+     * @param name - By a name.
+     */
     getProperty(name: string): Symbol | undefined;
+    /**
+     * Gets a property or returns undefined if it does not exist.
+     * @param findFunction - Function for searching for a property.
+     */
     getProperty(findFunction: (declaration: Symbol) => boolean): Symbol | undefined;
+    /** @internal */
+    getProperty(nameOrFindFunction: string | ((declaration: Symbol) => boolean)): Symbol | undefined;
     getProperty(nameOrFindFunction: string | ((declaration: Symbol) => boolean)): Symbol | undefined {
         return getSymbolByNameOrFindFunction(this.getProperties(), nameOrFindFunction);
     }

diff --git a/src/tests/compiler/type/typeTests.ts b/src/tests/compiler/type/typeTests.ts
@@ -1,5 +1,5 @@
 import { expect } from "chai";
-import { FunctionDeclaration, Node, Type, TypeAliasDeclaration, VariableStatement } from "../../../compiler";
+import { FunctionDeclaration, Node, Type, TypeAliasDeclaration, VariableStatement, Symbol } from "../../../compiler";
 import { VirtualFileSystemHost } from "../../../fileSystem";
 import { ObjectFlags, SymbolFlags, TypeFlags, TypeFormatFlags } from "../../../typescript";
 import { getInfoFromText } from "../testHelpers";
@@ -720,17 +720,48 @@ let unknownType: unknown;
         });
     });
 
+    describe(nameof<Type>(t => t.getPropertyOrThrow), () => {
+        function doTest(text: string, nameOrFindFunction: string | ((declaration: Symbol) => boolean), expected: string | undefined) {
+            const { firstType } = getTypeFromText(text);
+            if (expected == null)
+                expect(() => firstType.getPropertyOrThrow(nameOrFindFunction)).to.throw();
+            else
+                expect(firstType.getPropertyOrThrow(nameOrFindFunction).getName()).to.equal(expected);
+        }
+
+        it("should get the property by name", () => {
+            doTest("let myType: { str: string; other: number; };", "other", "other");
+        });
+
+        it("should get the property by function", () => {
+            doTest("let myType: { str: string; other: number; };", p => p.getName() === "other", "other");
+        });
+
+        it("should throw when not exists", () => {
+            doTest("let myType: { str: string; other: number; };", "test", undefined);
+        });
+    });
+
     describe(nameof<Type>(t => t.getProperty), () => {
+        function doTest(text: string, nameOrFindFunction: string | ((declaration: Symbol) => boolean), expected: string | undefined) {
+            const { firstType } = getTypeFromText(text);
+            const prop = firstType.getProperty(nameOrFindFunction);
+            if (expected == null)
+                expect(prop).to.be.undefined;
+            else
+                expect(prop!.getName()).to.equal(expected);
+        }
+
         it("should get the property by name", () => {
-            const { firstType } = getTypeFromText("let myType: { str: string; other: number; };");
-            const prop = firstType.getProperty("other")!;
-            expect(prop.getName()).to.equal("other");
+            doTest("let myType: { str: string; other: number; };", "other", "other");
         });
 
         it("should get the property by function", () => {
-            const { firstType } = getTypeFromText("let myType: { str: string; other: number; };");
-            const prop = firstType.getProperty(p => p.getName() === "other")!;
-            expect(prop.getName()).to.equal("other");
+            doTest("let myType: { str: string; other: number; };", p => p.getName() === "other", "other");
+        });
+
+        it("should return undefined when not exists", () => {
+            doTest("let myType: { str: string; other: number; };", "test", undefined);
         });
     });