VerifyTests · SimonCropp · Sep 30, 2026 · Sep 30, 2026 · Sep 30, 2026
diff --git a/.github/workflows/merge-dependabot.yml b/.github/workflows/merge-dependabot.yml
@@ -25,6 +25,9 @@ jobs:
       # Dependabot records the update type in its commit message metadata, for example
       # "update-type: version-update:semver-minor". A grouped bump lists one per dependency.
       # --match-head-commit refuses the merge if the branch moved after this build ran.
+      # A bump that conflicts with main (an earlier bump merged an adjacent line) is skipped:
+      # Dependabot rebases it, the rebase reruns Build, and that run triggers this workflow again.
+      # GitHub computes mergeability lazily, so UNKNOWN is retried briefly.
       - name: Merge when the bump is minor or patch
         env:
           GH_TOKEN: ${{ github.token }}
@@ -42,4 +45,13 @@ jobs:
             echo "::warning::No open pull request for $BRANCH"
             exit 0
           fi
+          for attempt in 1 2 3 4 5 6; do
+            mergeable=$(gh pr view "$pr" --json mergeable --jq '.mergeable')
+            [ "$mergeable" != "UNKNOWN" ] && break
+            sleep 5
+          done
+          if [ "$mergeable" = "CONFLICTING" ]; then
+            echo "::warning::Pull request #$pr conflicts with the base branch, leaving for Dependabot to rebase"
+            exit 0
+          fi
           gh pr merge "$pr" --squash --match-head-commit "$HEAD_SHA"
diff --git a/docs/comparer.md b/docs/comparer.md
@@ -415,7 +415,7 @@ Unsupported variants (16-bit, Adam7 interlacing) cause the decoder to throw. For
 ## Pre-packaged comparers
 
  * [Verify.AngleSharp.Diffing](https://github.com/VerifyTests/Verify.AngleSharp.Diffing): Comparison of html files via [AngleSharp.Diffing](https://github.com/AngleSharp/AngleSharp.Diffing).
- * [Verify.DiffPlex](https://github.com/VerifyTests/Verify.DiffPlex): Comparison of text via [DiffPlex](https://github.com/mmanela/diffplex).
+ * [Verify.DiffPlex](https://github.com/VerifyTests/Verify.DiffPlex): Comparison of text via [DiffPlex](https://github.com/mmanela/diffplex). Not required: a text diff is now shown by default. See [Text Diff Format](/docs/exception-message-format.md#text-diff-format).
  * [Verify.ICSharpCode.Decompiler](https://github.com/VerifyTests/Verify.ICSharpCode.Decompiler): Comparison of assemblies and types via [ICSharpCode.Decompiler](https://github.com/icsharpcode/ILSpy/wiki/Getting-Started-With-ICSharpCode.Decompiler).
  * [Verify.ImageHash](https://github.com/VerifyTests/Verify.ImageHash): Comparison of images via [ImageHash](https://github.com/coenm/ImageHash).
  * [Verify.ImageMagick](https://github.com/VerifyTests/Verify.ImageMagick): Verification and comparison of images via [Magick.NET](https://github.com/dlemstra/Magick.NET).

diff --git a/docs/exception-message-format.md b/docs/exception-message-format.md
@@ -51,6 +51,76 @@ The staged path lines are omitted when staging was unavailable (build server, or
 
 After the file listing, a `FileContent:` section includes the text content of new and not-equal files. This section is only present when there are text-based new or not-equal files. Binary files are listed in the file listing but their content is not included.
 
+A not-equal text file shows a `Diff:` of the verified text against the received text, rather than both texts in full. Lines compare exactly, whitespace and case included. When the texts differ only in something a line diff does not see, such as line endings, both texts are shown in full instead.
+
+
+### Text Diff Format
+
+The diff is produced by [DiffEngine](https://github.com/VerifyTests/DiffEngine)'s `TextDiff.Format`, in one of three formats:
+
+ * `Compact` (the default): the changed lines prefixed with `-` or `+`, each unchanged line next to a change prefixed with its received line number, and `[BOF]` or `[EOF]` where a change touches either end.
+ * `Full`: every line, prefixed with `-`, `+` or two spaces.
+ * `Minimal`: only the changed lines, prefixed with `-` or `+`.
+
+<!-- snippet: VerifyExceptionMessageBuilderTests.NotEqual_TextDiffCompact.verified.txt -->
+<a id='snippet-VerifyExceptionMessageBuilderTests.NotEqual_TextDiffCompact.verified.txt'></a>
+```txt
+Directory: {ProjectDirectory}
+NotEqual:
+  - Received: VerifyExceptionMessageBuilderTests.Fake.received.txt
+    Verified: VerifyExceptionMessageBuilderTests.Fake.verified.txt
+
+FileContent:
+
+NotEqual:
+
+Received: VerifyExceptionMessageBuilderTests.Fake.received.txt
+Verified: VerifyExceptionMessageBuilderTests.Fake.verified.txt
+Diff:
+2 line 2
+- line 3
++ line three
+4 line 4
+
+7 line 7
++ line 8
+  [EOF]
+```
+<sup><a href='/src/Verify.ExceptionParsing.Tests/VerifyExceptionMessageBuilderTests.NotEqual_TextDiffCompact.verified.txt#L1-L21' title='Snippet source file'>snippet source</a> | <a href='#snippet-VerifyExceptionMessageBuilderTests.NotEqual_TextDiffCompact.verified.txt' title='Start of snippet'>anchor</a></sup>
+<!-- endSnippet -->
+
+The format is set globally:
+
+<!-- snippet: UseTextDiffFormat -->
+<a id='snippet-UseTextDiffFormat'></a>
+```cs
+public static class ModuleInitializer
+{
+    [ModuleInitializer]
+    public static void Init() =>
+        VerifierSettings.UseTextDiffFormat(DiffEngine.TextDiffFormat.Full);
+}
+```
+<sup><a href='/src/ModuleInitDocs/UseTextDiffFormat.cs#L3-L12' title='Snippet source file'>snippet source</a> | <a href='#snippet-UseTextDiffFormat' title='Start of snippet'>anchor</a></sup>
+<!-- endSnippet -->
+
+To show both texts in full, as before diffs were shown, disable the diff:
+
+<!-- snippet: DisableTextDiff -->
+<a id='snippet-DisableTextDiff'></a>
+```cs
+public static class ModuleInitializer
+{
+    [ModuleInitializer]
+    public static void Init() =>
+        VerifierSettings.DisableTextDiff();
+}
+```
+<sup><a href='/src/ModuleInitDocs/DisableTextDiff.cs#L3-L12' title='Snippet source file'>snippet source</a> | <a href='#snippet-DisableTextDiff' title='Start of snippet'>anchor</a></sup>
+<!-- endSnippet -->
+
+This only changes the exception message. Launching a diff tool is controlled separately, by [DisableDiff](/docs/verify-options.md#disablediff).
+
 
 ## Example: All Categories
 
@@ -80,11 +150,14 @@ the new content
 NotEqual:
 
 Received: MyTests.Test2.received.txt
-received text
 Verified: MyTests.Test2.verified.txt
-verified text
+Diff:
+  [BOF]
+- verified text
++ received text
+  [EOF]
 ```
-<sup><a href='/src/Verify.ExceptionParsing.Tests/ExceptionMessageFormatSamples.AllCategories.verified.txt#L1-L27' title='Snippet source file'>snippet source</a> | <a href='#snippet-ExceptionMessageFormatSamples.AllCategories.verified.txt' title='Start of snippet'>anchor</a></sup>
+<sup><a href='/src/Verify.ExceptionParsing.Tests/ExceptionMessageFormatSamples.AllCategories.verified.txt#L1-L30' title='Snippet source file'>snippet source</a> | <a href='#snippet-ExceptionMessageFormatSamples.AllCategories.verified.txt' title='Start of snippet'>anchor</a></sup>
 <!-- endSnippet -->
 
 
@@ -163,17 +236,20 @@ inline expected
 NotEqual:
 
 Received: MyTests.Test1#01.received.txt
-received text
 Verified: MyTests.Test1#01.verified.txt
-verified text
+Diff:
+  [BOF]
+- verified text
++ received text
+  [EOF]
 ```
-<sup><a href='/src/Verify.ExceptionParsing.Tests/ExceptionMessageFormatSamples.InlineAndFileTogether.verified.txt#L1-L26' title='Snippet source file'>snippet source</a> | <a href='#snippet-ExceptionMessageFormatSamples.InlineAndFileTogether.verified.txt' title='Start of snippet'>anchor</a></sup>
+<sup><a href='/src/Verify.ExceptionParsing.Tests/ExceptionMessageFormatSamples.InlineAndFileTogether.verified.txt#L1-L29' title='Snippet source file'>snippet source</a> | <a href='#snippet-ExceptionMessageFormatSamples.InlineAndFileTogether.verified.txt' title='Start of snippet'>anchor</a></sup>
 <!-- endSnippet -->
 
 
 ### NotEqual with Comparer Message
 
-When a custom comparer provides a message, the content section uses `Compare Result:` instead of inline file content:
+When a custom comparer provides a message, the content section uses `Compare Result:` instead of a diff or the file content:
 
 <!-- snippet: ExceptionMessageFormatSamples.NotEqualWithMessage.verified.txt -->
 <a id='snippet-ExceptionMessageFormatSamples.NotEqualWithMessage.verified.txt'></a>

diff --git a/docs/mdsource/comparer.source.md b/docs/mdsource/comparer.source.md
@@ -136,7 +136,7 @@ Unsupported variants (16-bit, Adam7 interlacing) cause the decoder to throw. For
 ## Pre-packaged comparers
 
  * [Verify.AngleSharp.Diffing](https://github.com/VerifyTests/Verify.AngleSharp.Diffing): Comparison of html files via [AngleSharp.Diffing](https://github.com/AngleSharp/AngleSharp.Diffing).
- * [Verify.DiffPlex](https://github.com/VerifyTests/Verify.DiffPlex): Comparison of text via [DiffPlex](https://github.com/mmanela/diffplex).
+ * [Verify.DiffPlex](https://github.com/VerifyTests/Verify.DiffPlex): Comparison of text via [DiffPlex](https://github.com/mmanela/diffplex). Not required: a text diff is now shown by default. See [Text Diff Format](/docs/exception-message-format.md#text-diff-format).
  * [Verify.ICSharpCode.Decompiler](https://github.com/VerifyTests/Verify.ICSharpCode.Decompiler): Comparison of assemblies and types via [ICSharpCode.Decompiler](https://github.com/icsharpcode/ILSpy/wiki/Getting-Started-With-ICSharpCode.Decompiler).
  * [Verify.ImageHash](https://github.com/VerifyTests/Verify.ImageHash): Comparison of images via [ImageHash](https://github.com/coenm/ImageHash).
  * [Verify.ImageMagick](https://github.com/VerifyTests/Verify.ImageMagick): Verification and comparison of images via [Magick.NET](https://github.com/dlemstra/Magick.NET).

diff --git a/docs/mdsource/exception-message-format.source.md b/docs/mdsource/exception-message-format.source.md
@@ -44,6 +44,29 @@ The staged path lines are omitted when staging was unavailable (build server, or
 
 After the file listing, a `FileContent:` section includes the text content of new and not-equal files. This section is only present when there are text-based new or not-equal files. Binary files are listed in the file listing but their content is not included.
 
+A not-equal text file shows a `Diff:` of the verified text against the received text, rather than both texts in full. Lines compare exactly, whitespace and case included. When the texts differ only in something a line diff does not see, such as line endings, both texts are shown in full instead.
+
+
+### Text Diff Format
+
+The diff is produced by [DiffEngine](https://github.com/VerifyTests/DiffEngine)'s `TextDiff.Format`, in one of three formats:
+
+ * `Compact` (the default): the changed lines prefixed with `-` or `+`, each unchanged line next to a change prefixed with its received line number, and `[BOF]` or `[EOF]` where a change touches either end.
+ * `Full`: every line, prefixed with `-`, `+` or two spaces.
+ * `Minimal`: only the changed lines, prefixed with `-` or `+`.
+
+snippet: VerifyExceptionMessageBuilderTests.NotEqual_TextDiffCompact.verified.txt
+
+The format is set globally:
+
+snippet: UseTextDiffFormat
+
+To show both texts in full, as before diffs were shown, disable the diff:
+
+snippet: DisableTextDiff
+
+This only changes the exception message. Launching a diff tool is controlled separately, by [DisableDiff](/docs/verify-options.md#disablediff).
+
 
 ## Example: All Categories
 
@@ -63,7 +86,7 @@ snippet: ExceptionMessageFormatSamples.InlineAndFileTogether.verified.txt
 
 ### NotEqual with Comparer Message
 
-When a custom comparer provides a message, the content section uses `Compare Result:` instead of inline file content:
+When a custom comparer provides a message, the content section uses `Compare Result:` instead of a diff or the file content:
 
 snippet: ExceptionMessageFormatSamples.NotEqualWithMessage.verified.txt
 

diff --git a/docs/mdsource/verify-options.source.md b/docs/mdsource/verify-options.source.md
@@ -30,7 +30,7 @@ snippet: OnFluentHandlers
 
 ## OmitContentFromException
 
-By default, when a verify mismatch occurs for text, the content of the received and verified files is included in the exception that is thrown. This results in that text being included in test runners and build output. To omit the content use `VerifierSettings.OmitContentFromException`.
+By default, when a verify mismatch occurs for text, a diff of the received and verified files is included in the exception that is thrown. This results in that text being included in test runners and build output. To omit the content use `VerifierSettings.OmitContentFromException`. To change the diff format, or show both files in full, see [Text Diff Format](/docs/exception-message-format.md#text-diff-format).
 
 
 ## DisableDiff

diff --git a/docs/verify-options.md b/docs/verify-options.md
@@ -123,7 +123,7 @@ public Task OnFluentCallbacks() =>
 
 ## OmitContentFromException
 
-By default, when a verify mismatch occurs for text, the content of the received and verified files is included in the exception that is thrown. This results in that text being included in test runners and build output. To omit the content use `VerifierSettings.OmitContentFromException`.
+By default, when a verify mismatch occurs for text, a diff of the received and verified files is included in the exception that is thrown. This results in that text being included in test runners and build output. To omit the content use `VerifierSettings.OmitContentFromException`. To change the diff format, or show both files in full, see [Text Diff Format](/docs/exception-message-format.md#text-diff-format).
 
 
 ## DisableDiff

diff --git a/src/Directory.Packages.props b/src/Directory.Packages.props
@@ -7,7 +7,7 @@
     <PackageVersion Include="Argon" Version="0.37.0" />
     <PackageVersion Include="Argon.FSharp" Version="0.37.0" />
     <PackageVersion Include="BenchmarkDotNet" Version="0.15.8" />
-    <PackageVersion Include="DiffEngine" Version="20.5.2" />
+    <PackageVersion Include="DiffEngine" Version="20.6.0" />
     <PackageVersion Include="Expecto" Version="11.1.0" />
     <PackageVersion Include="Fixie" Version="4.2.0" />
     <PackageVersion Include="Fixie.TestAdapter" Version="4.2.0" />

diff --git a/src/ModuleInitDocs/DisableTextDiff.cs b/src/ModuleInitDocs/DisableTextDiff.cs
@@ -0,0 +1,13 @@
+public class DisableTextDiff
+{
+    #region DisableTextDiff
+
+    public static class ModuleInitializer
+    {
+        [ModuleInitializer]
+        public static void Init() =>
+            VerifierSettings.DisableTextDiff();
+    }
+
+    #endregion
+}
diff --git a/src/ModuleInitDocs/UseTextDiffFormat.cs b/src/ModuleInitDocs/UseTextDiffFormat.cs
@@ -0,0 +1,13 @@
+public class UseTextDiffFormat
+{
+    #region UseTextDiffFormat
+
+    public static class ModuleInitializer
+    {
+        [ModuleInitializer]
+        public static void Init() =>
+            VerifierSettings.UseTextDiffFormat(DiffEngine.TextDiffFormat.Full);
+    }
+
+    #endregion
+}
diff --git a/src/Verify.ExceptionParsing.Tests/ExceptionMessageFormatSamples.AllCategories.verified.txt b/src/Verify.ExceptionParsing.Tests/ExceptionMessageFormatSamples.AllCategories.verified.txt
@@ -21,7 +21,10 @@ the new content
 NotEqual:
 
 Received: MyTests.Test2.received.txt
-received text
 Verified: MyTests.Test2.verified.txt
-verified text
+Diff:
+  [BOF]
+- verified text
++ received text
+  [EOF]
 
diff --git a/...y.ExceptionParsing.Tests/ExceptionMessageFormatSamples.InlineAndFileTogether.verified.txt b/...y.ExceptionParsing.Tests/ExceptionMessageFormatSamples.InlineAndFileTogether.verified.txt
@@ -20,7 +20,10 @@ inline expected
 NotEqual:
 
 Received: MyTests.Test1#01.received.txt
-received text
 Verified: MyTests.Test1#01.verified.txt
-verified text
+Diff:
+  [BOF]
+- verified text
++ received text
+  [EOF]
 
diff --git a/src/Verify.ExceptionParsing.Tests/ExceptionParsingTests.MultipleItem.verified.txt b/src/Verify.ExceptionParsing.Tests/ExceptionParsingTests.MultipleItem.verified.txt
@@ -30,9 +30,12 @@ the content
 NotEqual:
 
 Received: ExceptionParsingTests.Fake.received.txt
-receivedText
 Verified: ExceptionParsingTests.Fake.verified.txt
-verifiedText
+Diff:
+  [BOF]
+- verifiedText
++ receivedText
+  [EOF]
 
 ,
   result: {

diff --git a/src/Verify.ExceptionParsing.Tests/ExceptionParsingTests.SingleItem.verified.txt b/src/Verify.ExceptionParsing.Tests/ExceptionParsingTests.SingleItem.verified.txt
@@ -23,9 +23,12 @@ the content
 NotEqual:
 
 Received: ExceptionParsingTests.Fake.received.txt
-receivedText
 Verified: ExceptionParsingTests.Fake.verified.txt
-verifiedText
+Diff:
+  [BOF]
+- verifiedText
++ receivedText
+  [EOF]
 
 ,
   result: {

diff --git a/src/Verify.ExceptionParsing.Tests/ExceptionParsingTests.SingleNotEqual.verified.txt b/src/Verify.ExceptionParsing.Tests/ExceptionParsingTests.SingleNotEqual.verified.txt
@@ -10,9 +10,12 @@ FileContent:
 NotEqual:
 
 Received: ExceptionParsingTests.Fake.received.txt
-receivedText
 Verified: ExceptionParsingTests.Fake.verified.txt
-verifiedText
+Diff:
+  [BOF]
+- verifiedText
++ receivedText
+  [EOF]
 
 ,
   result: {

diff --git a/...rify.ExceptionParsing.Tests/VerifyExceptionMessageBuilderTests.AllCategories.verified.txt b/...rify.ExceptionParsing.Tests/VerifyExceptionMessageBuilderTests.AllCategories.verified.txt
@@ -21,7 +21,10 @@ new content
 NotEqual:
 
 Received: VerifyExceptionMessageBuilderTests.Fake.received.txt
-received
 Verified: VerifyExceptionMessageBuilderTests.Fake.verified.txt
-verified
+Diff:
+  [BOF]
+- verified
++ received
+  [EOF]
 
diff --git a/...VerifyExceptionMessageBuilderTests.MultipleNotEqual_MixedMessageAndNoMessage.verified.txt b/...VerifyExceptionMessageBuilderTests.MultipleNotEqual_MixedMessageAndNoMessage.verified.txt
@@ -10,9 +10,12 @@ FileContent:
 NotEqual:
 
 Received: VerifyExceptionMessageBuilderTests.Fake.received.txt
-received text
 Verified: VerifyExceptionMessageBuilderTests.Fake.verified.txt
-verified text
+Diff:
+  [BOF]
+- verified text
++ received text
+  [EOF]
 
 Received: VerifyExceptionMessageBuilderTests.Fake.received.txt
 Verified: VerifyExceptionMessageBuilderTests.Fake.verified.txt

diff --git a/...ionParsing.Tests/VerifyExceptionMessageBuilderTests.NotEqual_TextDiffCompact.verified.txt b/...ionParsing.Tests/VerifyExceptionMessageBuilderTests.NotEqual_TextDiffCompact.verified.txt
@@ -0,0 +1,21 @@
+Directory: {ProjectDirectory}
+NotEqual:
+  - Received: VerifyExceptionMessageBuilderTests.Fake.received.txt
+    Verified: VerifyExceptionMessageBuilderTests.Fake.verified.txt
+
+FileContent:
+
+NotEqual:
+
+Received: VerifyExceptionMessageBuilderTests.Fake.received.txt
+Verified: VerifyExceptionMessageBuilderTests.Fake.verified.txt
+Diff:
+2 line 2
+- line 3
++ line three
+4 line 4
+
+7 line 7
++ line 8
+  [EOF]
+