Calculate the difference between the subject and the expected nearby …

…time
fluentassertions · Oct 14, 2022 · 027f789 · 027f789
1 parent 70a0793
commit 027f789
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Showing 4 changed files with 27 additions and 15 deletions.
diff --git a/Src/FluentAssertions/Primitives/DateTimeAssertions.cs b/Src/FluentAssertions/Primitives/DateTimeAssertions.cs
@@ -168,12 +168,18 @@ public AndConstraint<TAssertions> Be(DateTime? expected, string because = "", pa
         long distanceToMaxInTicks = (DateTime.MaxValue - nearbyTime).Ticks;
         DateTime maximumValue = nearbyTime.AddTicks(Math.Min(precision.Ticks, distanceToMaxInTicks));
 
+        var difference = (Subject - nearbyTime)?.Duration();
+
         Execute.Assertion
-            .ForCondition((Subject >= minimumValue) && (Subject.Value <= maximumValue))
             .BecauseOf(because, becauseArgs)
-            .FailWith("Expected {context:the date and time} to be within {0} from {1}{reason}, but found {2}.",
-                precision,
-                nearbyTime, Subject);
+            .WithExpectation("Expected {context:the date and time} to be within {0} from {1}{reason}", precision, nearbyTime)
+            .ForCondition(Subject is not null)
+            .FailWith(", but found <null>.")
+            .Then
+            .ForCondition((Subject >= minimumValue) && (Subject <= maximumValue))
+            .FailWith(", but {0} is off by {1}.", Subject, difference)
+            .Then
+            .ClearExpectation();
 
         return new AndConstraint<TAssertions>((TAssertions)this);
     }

diff --git a/Src/FluentAssertions/Primitives/DateTimeOffsetAssertions.cs b/Src/FluentAssertions/Primitives/DateTimeOffsetAssertions.cs
@@ -304,12 +304,18 @@ public DateTimeOffsetAssertions(DateTimeOffset? value)
         long distanceToMaxInTicks = (DateTimeOffset.MaxValue - nearbyTime).Ticks;
         DateTimeOffset maximumValue = nearbyTime.AddTicks(Math.Min(precision.Ticks, distanceToMaxInTicks));
 
+        var differnece = (Subject - nearbyTime)?.Duration();
+
         Execute.Assertion
-            .ForCondition(Subject >= minimumValue && (Subject <= maximumValue))
             .BecauseOf(because, becauseArgs)
-            .FailWith("Expected {context:the date and time} to be within {0} from {1}{reason}, but it was {2}.",
-                precision,
-                nearbyTime, Subject);
+            .WithExpectation("Expected {context:the date and time} to be within {0} from {1}{reason}", precision, nearbyTime)
+            .ForCondition(Subject is not null)
+            .FailWith(", but found <null>.")
+            .Then
+            .ForCondition(Subject >= minimumValue && Subject <= maximumValue)
+            .FailWith(", but {0} is off by {1}.", Subject, differnece)
+            .Then
+            .ClearExpectation();
 
         return new AndConstraint<TAssertions>((TAssertions)this);
     }

diff --git a/Tests/FluentAssertions.Specs/Primitives/DateTimeAssertionSpecs.cs b/Tests/FluentAssertions.Specs/Primitives/DateTimeAssertionSpecs.cs
@@ -483,7 +483,7 @@ public void When_asserting_subject_datetime_is_close_to_another_value_that_is_la
             // Assert
             act.Should().Throw<XunitException>()
                 .WithMessage(
-                    "Expected time to be within 20ms from <2012-03-13 12:15:31>, but found <2012-03-13 12:15:30.979>.");
+                    "Expected time to be within 20ms from <2012-03-13 12:15:31>, but <2012-03-13 12:15:30.979> is off by 21ms.");
         }
 
         [Fact]
@@ -499,7 +499,7 @@ public void When_asserting_subject_datetime_is_close_to_another_value_that_is_la
             // Assert
             act.Should().Throw<XunitException>()
                 .WithMessage(
-                    "Expected time to be within 20ms from <2012-03-13 12:15:31>, but found <2012-03-13 12:15:30.979>.");
+                    "Expected time to be within 20ms from <2012-03-13 12:15:31>, but <2012-03-13 12:15:30.979> is off by 21ms.");
         }
 
         [Fact]
@@ -515,7 +515,7 @@ public void When_asserting_subject_datetime_is_close_to_another_value_that_is_ea
             // Assert
             act.Should().Throw<XunitException>()
                 .WithMessage(
-                    "Expected time to be within 20ms from <2012-03-13 12:15:31>, but found <2012-03-13 12:15:31.021>.");
+                    "Expected time to be within 20ms from <2012-03-13 12:15:31>, but <2012-03-13 12:15:31.021> is off by 21ms.");
         }
 
         [Fact]

diff --git a/Tests/FluentAssertions.Specs/Primitives/DateTimeOffsetAssertionSpecs.cs b/Tests/FluentAssertions.Specs/Primitives/DateTimeOffsetAssertionSpecs.cs
@@ -661,7 +661,7 @@ public void When_asserting_subject_datetimeoffset_is_close_to_another_value_that
             // Assert
             act.Should().Throw<XunitException>()
                 .WithMessage(
-                    "Expected time to be within 20ms from <2012-03-13 12:15:31 +1H>, but it was <2012-03-13 12:15:30.979 +1H>.");
+                    "Expected time to be within 20ms from <2012-03-13 12:15:31 +1H>, but <2012-03-13 12:15:30.979 +1H> is off by 21ms.");
         }
 
         [Fact]
@@ -677,7 +677,7 @@ public void When_asserting_subject_datetimeoffset_is_close_to_another_value_that
             // Assert
             act.Should().Throw<XunitException>()
                 .WithMessage(
-                    "Expected time to be within 20ms from <2012-03-13 12:15:31 +1h>, but it was <2012-03-13 12:15:31.021 +1h>.");
+                    "Expected time to be within 20ms from <2012-03-13 12:15:31 +1h>, but <2012-03-13 12:15:31.021 +1h> is off by 21ms.");
         }
 
         [Fact]
@@ -693,7 +693,7 @@ public void When_asserting_subject_datetimeoffset_is_close_to_another_value_that
             // Assert
             act.Should().Throw<XunitException>()
                 .WithMessage(
-                    "Expected time to be within 35ms from <2012-03-13 12:15:31 +1h>, but it was <2012-03-13 12:15:31.036 +1h>.");
+                    "Expected time to be within 35ms from <2012-03-13 12:15:31 +1h>, but <2012-03-13 12:15:31.036 +1h> is off by 36ms.");
         }
 
         [Fact]
@@ -722,7 +722,7 @@ public void When_asserting_subject_null_datetimeoffset_is_close_to_another_it_sh
 
             // Assert
             act.Should().Throw<XunitException>()
-                .WithMessage("Expected*, but it was <null>.");
+                .WithMessage("Expected*, but found <null>.");
         }
 
         [Fact]