[tests] Fix some tests for web numbers and dart2js production mode

Change-Id: I05a1814f2a2c5810f75708ba72bfafe137122f67
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/332486
Commit-Queue: Stephen Adams <sra@google.com>
Reviewed-by: Mark Zhou <markzipan@google.com>

tests/language/function_subtype/bound_closure7_test.dart

@@ -23,13 +23,18 @@ void main() {
   Expect.isTrue(f is Foo<Foo<int>>);
   Expect.isFalse(f is Foo<int>);
   Expect.isFalse(f is Foo<Object>);
-  Expect.throwsTypeError(() => f(f));
+  if (!dart2jsProductionMode) {
-  Expect.throwsTypeError(() => f(42));
+    Expect.throwsTypeError(() => f(f));
+    Expect.throwsTypeError(() => f(42));
+  }
 
   Foo<Foo<int>> bazInt = baz; // implicit instantiation baz<int>
   f = bazInt;
   Expect.isTrue(f(bar));
   Expect.isFalse(f is Foo<int>);
-  Expect.throwsTypeError(() => f(f));
+
-  Expect.throwsTypeError(() => f(42));
+  if (!dart2jsProductionMode) {
+    Expect.throwsTypeError(() => f(f));
+    Expect.throwsTypeError(() => f(42));
+  }
 }

tests/language/function_subtype/checked0_test.dart

@@ -30,7 +30,7 @@ class C<T> {
   void test(String nameOfT, bool expectedResult) {
     check(bool expectedResult, f()) {
       if (!expectedResult) {
-        Expect.throwsTypeError(f);
+        if (!dart2jsProductionMode) Expect.throwsTypeError(f);
       } else {
         f();
       }

tests/language/identity/closure2_test.dart

@@ -8,13 +8,21 @@ var myIdentical = identical;
 
 main() {
   // Mint (2^63).
-  // TODO(rnystrom): Figure out how to change this to work on the web.
   Expect.isTrue(myIdentical(0x8000000000000000, 0x8000000000000000));
-  Expect.isFalse(myIdentical(0x8000000000000000, 0x8000000000000001));
 
-  // Different types.
+  if (!webNumbers) {
-  Expect.isFalse(myIdentical(42, 42.0));
+    Expect.isFalse(myIdentical(0x8000000000000000, 0x8000000000000000 + 1));
 
-  // NaN handling.
+    // Different types.
-  Expect.isTrue(myIdentical(double.nan, double.nan));
+    Expect.isFalse(myIdentical(42, 42.0));
+
+    // NaN handling.
+    Expect.isTrue(myIdentical(double.nan, double.nan));
+  } else {
+    // Web numbers have less precision, conflate int and double values, and have
+    // an incorrect implementation of `identical` for NaNs.
+    Expect.isTrue(myIdentical(0x8000000000000000, 0x8000000000000000 + 1));
+    Expect.isTrue(myIdentical(42, 42.0));
+    Expect.isFalse(myIdentical(double.nan, double.nan));
+  }
 }

tests/language/identity/closure_test.dart

@@ -41,4 +41,7 @@ main() {
   // Null handling.
   Expect.isFalse(myIdentical(42, null));
   Expect.isTrue(myIdentical(null, null));
+
+  // Assigning to the variable prevents dart2js from optimizing calls.
+  myIdentical = identical;
 }

tests/language/identity/nan_identical_test.dart

@@ -20,6 +20,22 @@ double createOtherNAN() {
 }
 
 main() {
+  if (webNumbers) {
+    // (1) The web compilers elect to generate smaller, faster code for
+    // `identical` using `===`, with the result that `identical(NaN, NaN)` is
+    // false.
+    //
+    // (2) In JavaScript different NaN values are treated the same by
+    // `Object.is`, and can only be distinguished by writing the bits into typed
+    // data, making it costly to compare NaN values.
+
+    // Validate current behaviour so we will be alerted if (1) changes.
+    Expect.isFalse(checkIdentical(double.nan, -double.nan));
+    Expect.isFalse(checkIdentical(double.nan, double.nan));
+    Expect.isFalse(checkIdentical(-double.nan, -double.nan));
+    return;
+  }
+
   var otherNAN = createOtherNAN();
   for (int i = 0; i < 100; i++) {
     Expect.isFalse(checkIdentical(double.nan, -double.nan));