feat(sdk): add clear() method for MutArray

docs/api/04-standard-library/std/array.md

@@ -204,6 +204,7 @@ Mutable Array.
 | **Name** | **Description** |
 | --- | --- |
 | <code><a href="#@winglang/sdk.std.MutArray.at">at</a></code> | Get the value at the given index. |
+| <code><a href="#@winglang/sdk.std.MutArray.clear">clear</a></code> | Removes all elements. |
 | <code><a href="#@winglang/sdk.std.MutArray.concat">concat</a></code> | Merge arr to the end of this array. |
 | <code><a href="#@winglang/sdk.std.MutArray.contains">contains</a></code> | Checks if this array includes searchElement. |
 | <code><a href="#@winglang/sdk.std.MutArray.copy">copy</a></code> | Create an immutable shallow copy of this array. |
@@ -236,6 +237,14 @@ index of the value to get.
 
 ---
 
+##### `clear` <a name="clear" id="@winglang/sdk.std.MutArray.clear"></a>
+
+```wing
+clear(): void
+```
+
+Removes all elements.
+
 ##### `concat` <a name="concat" id="@winglang/sdk.std.MutArray.concat"></a>
 
 ```wing

packages/@winglang/sdk/src/std/array.ts

@@ -165,6 +165,16 @@ export class MutArray {
     throw new Error("Abstract");
   }
 
+  /**
+   * Removes all elements
+   *
+   * @macro $self$.length = 0;
+   *
+   */
+  public clear(): void {
+    throw new Error("Macro");
+  }
+
   /**
    * Get the value at the given index
    * @macro ((arr, index) => { if (index < 0 || index >= arr.length) throw new Error("Index out of bounds"); return arr[index]; })($self$, $args$)

tests/sdk_tests/std/array.test.w

@@ -19,6 +19,39 @@ test "length" {
   assert(MutArray<str>["hello"].length == 1);
 }
 
+//-----------------------------------------------------------------------------
+// clear()
+
+test "clear()" {
+  let arr = MutArray<str>["hello", "world", "wingcloud"];
+  assert(arr.length == 3);
+
+  arr.clear();
+
+  assert(arr.length == 0);
+
+  // Verify that accessing elements throws an error
+  let assertThrows = (expected: str, block: (): void) => {
+    let var error = false;
+    try {
+      block();
+    } catch actual {
+      assert(actual == expected);
+      error = true;
+    }
+    assert(error);
+  };
+
+  assertThrows("Index out of bounds", () => {
+    arr.at(0);
+  });
+
+  // Verify that we can add new elements after clearing
+  arr.push("new element");
+  assert(arr.length == 1);
+  assert(arr.at(0) == "new element");
+}
+
 //-----------------------------------------------------------------------------
 // at()
 

tools/hangar/__snapshots__/test_corpus/sdk_tests/std/array.test.w_test_sim.md

@@ -3,6 +3,7 @@
 ## stdout.log
 ```log
 pass ─ array.test.wsim » root/Default/test:at()                      
+pass ─ array.test.wsim » root/Default/test:clear()                   
 pass ─ array.test.wsim » root/Default/test:concatArray()             
 pass ─ array.test.wsim » root/Default/test:concatMutArray()          
 pass ─ array.test.wsim » root/Default/test:contains()                
@@ -21,7 +22,7 @@ pass ─ array.test.wsim » root/Default/test:removeFirst()
 pass ─ array.test.wsim » root/Default/test:set()                     
 pass ─ array.test.wsim » root/Default/test:slice()                   
 
-Tests 18 passed (18)
+Tests 19 passed (19)
 Snapshots 1 skipped
 Test Files 1 passed (1)
 Duration <DURATION>