feat(ngError): add error message compression and better error messages

- add toThrowNg matcher

1 files changed, 80 insertions, 0 deletions

diff --git a/test/ngErrorSpec.js b/test/ngErrorSpec.js
new file mode 100644
index 00000000..81773322
--- /dev/null
+++ b/test/ngErrorSpec.js
@@ -0,0 +1,80 @@
+'use strict';
+
+describe('ngError', function() {
+
+  var supportStackTraces = function() {
+    var e = new Error();
+    return isDefined(e.stack);
+  };
+
+  it('should return an Error instance', function() {
+    var myError = ngError();
+    expect(myError instanceof Error).toBe(true);
+  });
+
+
+  it('should generate stack trace at the frame where ngError was called', function() {
+    var myError;
+
+    function someFn() {
+      function nestedFn() {
+        myError = ngError(0, "I fail!");
+      }
+      nestedFn();
+    }
+
+    someFn();
+
+    // only Chrome, Firefox have stack
+    if (!supportStackTraces()) return;
+
+    expect(myError.stack).toMatch(/^[.\s\S]+nestedFn[.\s\S]+someFn.+/);
+  });
+
+
+  it('should interpolate string arguments without quotes', function() {
+    var myError = ngError(26, 'This {0} is "{1}"', 'foo', 'bar');
+    expect(myError.message).toBe('[NgErr26] This foo is "bar"');
+  });
+
+
+  it('should interpolate non-string arguments', function() {
+    var arr = [1, 2, 3],
+        obj = {a: 123, b: 'baar'},
+        anonFn = function(something) { return something; },
+        namedFn = function foo(something) { return something; },
+        myError;
+
+    myError = ngError(26, 'arr: {0}; obj: {1}; anonFn: {2}; namedFn: {3}',
+                               arr,      obj,      anonFn,      namedFn);
+
+    expect(myError.message).toContain('[NgErr26] arr: [1,2,3]; obj: {"a":123,"b":"baar"};');
+    // IE does not add space after "function"
+    expect(myError.message).toMatch(/anonFn: function\s?\(something\);/);
+    expect(myError.message).toContain('namedFn: function foo(something)');
+  });
+
+
+  it('should not suppress falsy objects', function() {
+    var myError = ngError(26, 'false: {0}; zero: {1}; null: {2}; undefined: {3}; emptyStr: {4}',
+                                   false,      0,         null,      undefined,      '');
+    expect(myError.message).
+        toBe('[NgErr26] false: false; zero: 0; null: null; undefined: undefined; emptyStr: ');
+  });
+
+
+  it('should preserve interpolation markers when fewer arguments than needed are provided', function() {
+    // this way we can easily see if we are passing fewer args than needed
+
+    var foo = 'Fooooo',
+        myError = ngError(26, 'This {0} is {1} on {2}', foo);
+
+    expect(myError.message).toBe('[NgErr26] This Fooooo is {1} on {2}');
+  });
+
+
+  it('should pass through the message if no interpolation is needed', function() {
+    var myError = ngError(26, 'Something horrible happened!');
+    expect(myError.message).toBe('[NgErr26] Something horrible happened!');
+  });
+});