Added support of Empty operator for xUnit, MsTest and MbUnit

RELEASE_NOTES.md

@@ -4,7 +4,8 @@
 * Enable substring checks https://github.com/fsprojects/FsUnit/pull/45
 * Fixed assertion message for NUnit equal constraint - https://github.com/fsprojects/FsUnit/pull/60
 * Added support of `shouldFail` operator for xUnit, MsTest and MbUnit - https://github.com/fsprojects/FsUnit/pull/64
-* Added support of `instanceOfType` operator for xUnit, MsTest and MbUnit -
+* Added support of `instanceOfType` operator for xUnit, MsTest and MbUnit - https://github.com/fsprojects/FsUnit/pull/65
+* Added support of `Empty` operator for xUnit, MsTest and MbUnit -
 
 ### 1.3.1.0 - 26 July 2015
 * Bump NUnit version up to 2.6.4

docs/content/operators.md

@@ -4,7 +4,7 @@ Operators comparison across frameworks
 | Operator               | NUnit | xUnit | MSTest | MbUnit |
 |------------------------|:-----:|:-----:|:------:|:------:|
 | `Null`                 | +     | +     | +      | +      |
-| `Empty`                | +     |       |        |        |
+| `Empty`                | +     | +     | +      | +      |
 | `EmptyString`          | +     | +     | +      | +      |
 | `NullOrEmptyString`    | +     | +     | +      | +      |
 | `True`                 | +     | +     | +      | +      |

src/FsUnit.MbUnit/FsUnit.fs

@@ -37,6 +37,8 @@ let be = CustomMatchers.be
 
 let Null = CustomMatchers.Null
 
+let Empty = CustomMatchers.Empty
+
 let EmptyString = CustomMatchers.EmptyString
 
 let NullOrEmptyString = CustomMatchers.NullOrEmptyString

src/FsUnit.MsTestUnit/FsUnit.fs

@@ -47,6 +47,8 @@ let be = CustomMatchers.be
 
 let Null = CustomMatchers.Null
 
+let Empty = CustomMatchers.Empty
+
 let EmptyString = CustomMatchers.EmptyString
 
 let NullOrEmptyString = CustomMatchers.NullOrEmptyString

src/FsUnit.Xunit/CustomMatchers.fs

@@ -44,6 +44,15 @@ let be = id
 
 let Null = Is.Null()
 
+let Empty = CustomMatcher<obj>("A non empty", fun o ->
+                match o with
+                | :? string as s    -> s.Trim() = ""
+                | :? list<_> as l   -> List.isEmpty l
+                | :? array<_> as a  -> Array.isEmpty a
+                | :? seq<_> as s    -> Seq.isEmpty s
+                | :? System.Collections.IEnumerable as e -> e |> Seq.cast |> Seq.isEmpty
+                | _ -> false)
+
 let EmptyString = CustomMatcher<obj>("A non empty string", fun s -> (string s).Trim() = "")
 
 let NullOrEmptyString = CustomMatcher<obj>("A not empty or not null string", fun s -> String.IsNullOrEmpty(unbox s))

src/FsUnit.Xunit/FsUnit.fs

@@ -51,6 +51,8 @@ let be = CustomMatchers.be
 
 let Null = CustomMatchers.Null
 
+let Empty = CustomMatchers.Empty
+
 let EmptyString = CustomMatchers.EmptyString
 
 let NullOrEmptyString = CustomMatchers.NullOrEmptyString

tests/FsUnit.MbUnit.Test/beEmptyTests.fs

@@ -7,25 +7,50 @@ open NHamcrest.Core
 type ``be Empty tests`` ()=
     [<Test>] member test.
      ``empty List should be Empty`` ()=
-        [].IsEmpty |> should be True
+        [] |> should be Empty
+
+    [<Test>] member test.
+     ``non-empty List should fail to be Empty`` ()=
+        shouldFail (fun () -> [1] |> should be Empty)
 
     [<Test>] member test.
      ``non-empty List should not be Empty`` ()=
-        [1].IsEmpty |> should not' (be True)
+        [1] |> should not' (be Empty)
+
+    [<Test>] member test.
+     ``empty List should fail to not be Empty`` ()=
+        shouldFail (fun () -> [] |> should not' (be Empty))
 
     [<Test>] member test.
      ``empty Array should be Empty`` ()=
-        [||] |> Array.isEmpty |> should be True
+        [||] |> should be Empty
+
+    [<Test>] member test.
+     ``non-empty Array should fail to be Empty`` ()=
+        shouldFail (fun () -> [|1|] |> should be Empty)
 
     [<Test>] member test.
      ``non-empty Array should not be Empty`` ()=
-        [|1|] |> Array.isEmpty |> should not' (be True)
+        [|1|] |> should not' (be Empty)
+
+    [<Test>] member test.
+     ``empty Array should fail to not be Empty`` ()=
+        shouldFail (fun () -> [||] |> should not' (be Empty))
 
     [<Test>] member test.
      ``empty Seq should be Empty`` ()=
-        Seq.empty |> Seq.isEmpty |> should be True
+        Seq.empty |> should be Empty
+
+    [<Test>] member test.
+     ``non-empty Seq should fail to be Empty`` ()=
+        shouldFail (fun () -> seq { yield 1 } |> should be Empty)
 
     [<Test>] member test.
      ``non-empty Seq should not be Empty`` ()=
-        seq { yield 1 } |> Seq.isEmpty |> should not' (be True)
+        seq { yield 1 } |> should not' (be Empty)
+
+    [<Test>] member test.
+     ``empty Seq should fail to not be Empty`` ()=
+        shouldFail (fun () -> Seq.empty |> should not' (be Empty))
+
 

tests/FsUnit.MsTest.Test/beEmptyTests.fs

@@ -7,25 +7,49 @@ open NHamcrest.Core
 type ``be Empty tests`` ()=
     [<TestMethod>] member test.
      ``empty List should be Empty`` ()=
-        [].IsEmpty |> should be True
+        [] |> should be Empty
+
+    [<TestMethod>] member test.
+     ``non-empty List should fail to be Empty`` ()=
+        shouldFail (fun () -> [1] |> should be Empty)
 
     [<TestMethod>] member test.
      ``non-empty List should not be Empty`` ()=
-        [1].IsEmpty |> should not' (be True)
+        [1] |> should not' (be Empty)
+
+    [<TestMethod>] member test.
+     ``empty List should fail to not be Empty`` ()=
+        shouldFail (fun () -> [] |> should not' (be Empty))
 
     [<TestMethod>] member test.
      ``empty Array should be Empty`` ()=
-        [||] |> Array.isEmpty |> should be True
+        [||] |> should be Empty
+
+    [<TestMethod>] member test.
+     ``non-empty Array should fail to be Empty`` ()=
+        shouldFail (fun () -> [|1|] |> should be Empty)
 
     [<TestMethod>] member test.
      ``non-empty Array should not be Empty`` ()=
-        [|1|] |> Array.isEmpty |> should not' (be True)
+        [|1|] |> should not' (be Empty)
+
+    [<TestMethod>] member test.
+     ``empty Array should fail to not be Empty`` ()=
+        shouldFail (fun () -> [||] |> should not' (be Empty))
 
     [<TestMethod>] member test.
      ``empty Seq should be Empty`` ()=
-        Seq.empty |> Seq.isEmpty |> should be True
+        Seq.empty |> should be Empty
+
+    [<TestMethod>] member test.
+     ``non-empty Seq should fail to be Empty`` ()=
+        shouldFail (fun () -> seq { yield 1 } |> should be Empty)
 
     [<TestMethod>] member test.
      ``non-empty Seq should not be Empty`` ()=
-        seq { yield 1 }  |> Seq.isEmpty |> should not' (be True)
+        seq { yield 1 } |> should not' (be Empty)
+
+    [<TestMethod>] member test.
+     ``empty Seq should fail to not be Empty`` ()=
+        shouldFail (fun () -> Seq.empty |> should not' (be Empty))
 

tests/FsUnit.Xunit.Test/beEmptyTests.fs

@@ -6,25 +6,50 @@ open NHamcrest.Core
 type ``be Empty tests`` ()=
     [<Fact>] member test.
      ``empty List should be Empty`` ()=
-        [].IsEmpty |> should be True
+        [] |> should be Empty
+
+    [<Fact>] member test.
+     ``non-empty List should fail to be Empty`` ()=
+        shouldFail (fun () -> [1] |> should be Empty)
 
     [<Fact>] member test.
      ``non-empty List should not be Empty`` ()=
-        [1].IsEmpty |> should not' (be True)
+        [1] |> should not' (be Empty)
+
+    [<Fact>] member test.
+     ``empty List should fail to not be Empty`` ()=
+        shouldFail (fun () -> [] |> should not' (be Empty))
 
     [<Fact>] member test.
      ``empty Array should be Empty`` ()=
-        [||] |> Array.isEmpty |> should be True
+        [||] |> should be Empty
+
+    [<Fact>] member test.
+     ``non-empty Array should fail to be Empty`` ()=
+        shouldFail (fun () -> [|1|] |> should be Empty)
 
     [<Fact>] member test.
      ``non-empty Array should not be Empty`` ()=
-        [|1|] |> Array.isEmpty |> should not' (be True)
+        [|1|] |> should not' (be Empty)
+
+    [<Fact>] member test.
+     ``empty Array should fail to not be Empty`` ()=
+        shouldFail (fun () -> [||] |> should not' (be Empty))
 
     [<Fact>] member test.
      ``empty Seq should be Empty`` ()=
-        Seq.empty |> Seq.isEmpty |> should be True
+        Seq.empty |> should be Empty
+
+    [<Fact>] member test.
+     ``non-empty Seq should fail to be Empty`` ()=
+        shouldFail (fun () -> seq { yield 1 } |> should be Empty)
 
     [<Fact>] member test.
      ``non-empty Seq should not be Empty`` ()=
-        seq { yield 1 }  |> Seq.isEmpty |> should not' (be True)
+        seq { yield 1 } |> should not' (be Empty)
+
+    [<Fact>] member test.
+     ``empty Seq should fail to not be Empty`` ()=
+        shouldFail (fun () -> Seq.empty |> should not' (be Empty))
+