Multliline expectations

- Add else.project test
- Use normalizeWindowsOutput
- Add a changelog entry
- Update expectation
- Use concatOutput on needle
- Include output
- Align lines
- Show modified output
- Apply concatOutput to the needle
- Show start and end of lines with ASCII ^ and $h
- Can't print pilcrow so use grep char for marking end of line
- Marking the start of line distinguishes "expected" intro from its content too, same for "output"
- Use \n in multiline string expectation

cabal-testsuite/PackageTests/ConditionalAndImport/cabal.test.hs

@@ -1,8 +1,5 @@
 import Test.Cabal.Prelude
 
-normalizeWindowsOutput :: String -> String
-normalizeWindowsOutput = if isWindows then map (\x -> case x of '/' -> '\\'; _ -> x) else id
-
 main = cabalTest . withRepo "repo" . recordMode RecordMarked $ do
   let log = recordHeader . pure
 

cabal-testsuite/PackageTests/ProjectImport/ParseErrorProvenance/cabal.out

@@ -0,0 +1,2 @@
+# cabal v2-build
+Warning: <ROOT>/else.project, else.project: Unrecognized section '_' on line 3

cabal-testsuite/PackageTests/ProjectImport/ParseErrorProvenance/cabal.test.hs

@@ -0,0 +1,15 @@
+import Test.Cabal.Prelude
+
+main = cabalTest . recordMode RecordMarked $ do
+  let log = recordHeader . pure
+
+  outElse <- fails $ cabal' "v2-build" [ "all", "--dry-run", "--project-file=else.project" ]
+  assertOutputContainsOn unConcatOutput unConcatOutput concatOutput
+    (concatOutput "When using configuration from:\n\
+    \  - else.project\n\
+    \  - dir-else/else.config\n\
+    \The following errors occurred:\n\
+    \  - The package location 'no-pkg-here' does not exist.")
+    outElse
+
+  return ()

cabal-testsuite/PackageTests/ProjectImport/ParseErrorProvenance/dir-else/else.config

@@ -0,0 +1,4 @@
+if false
+else
+    _
+    packages: no-pkg-here

cabal-testsuite/PackageTests/ProjectImport/ParseErrorProvenance/else.project

@@ -0,0 +1 @@
+import: dir-else/else.config

cabal-testsuite/src/Test/Cabal/Prelude.hs

@@ -3,6 +3,7 @@
 {-# LANGUAGE NondecreasingIndentation #-}
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE CPP #-}
+{-# LANGUAGE ViewPatterns #-}
 
 -- | Generally useful definitions that we expect most test scripts
 -- to use.
@@ -795,19 +796,31 @@ recordMode mode = withReaderT (\env -> env {
     testRecordUserMode = Just mode
     })
 
-assertOutputContains :: MonadIO m => WithCallStack (String -> Result -> m ())
-assertOutputContains needle result =
+assertOutputContainsOn :: MonadIO m => WithCallStack ((String -> String) -> (String -> String) -> (String -> String) -> (String -> String) -> String -> Result -> m ())
+assertOutputContainsOn unN n unO o (n -> needle) (o . resultOutput -> output) =
     withFrozenCallStack $
-    unless (needle `isInfixOf` (concatOutput output)) $
-    assertFailure $ " expected: " ++ needle
-  where output = resultOutput result
+    unless (n needle `isInfixOf` output) $
+    assertFailure $ "expected:\n" ++ unN needle ++
+                    "\nin output:\n" ++ unO output
 
-assertOutputDoesNotContain :: MonadIO m => WithCallStack (String -> Result -> m ())
-assertOutputDoesNotContain needle result =
+assertOutputDoesNotContainOn :: MonadIO m => WithCallStack ((String -> String) -> (String -> String) -> (String -> String) -> (String -> String) -> String -> Result -> m ())
+assertOutputDoesNotContainOn unN n unO o (n -> needle) (o . resultOutput -> output) =
     withFrozenCallStack $
-    when (needle `isInfixOf` (concatOutput output)) $
-    assertFailure $ "unexpected: " ++ needle
-  where output = resultOutput result
+    when (needle `isInfixOf` output) $
+    assertFailure $ "unexpected:\n" ++ unN needle ++
+                    "\nin output:\n" ++ unO output
+
+assertOutputContains :: MonadIO m => WithCallStack (String -> Result -> m ())
+assertOutputContains = assertOutputContainsOn id id unConcatOutput concatOutput
+
+assertOutputDoesNotContain :: MonadIO m => WithCallStack (String -> Result -> m ())
+assertOutputDoesNotContain = assertOutputDoesNotContainOn id id unConcatOutput concatOutput
+
+assertOutputContainsMultiline :: MonadIO m => WithCallStack (String -> Result -> m ())
+assertOutputContainsMultiline = assertOutputContainsOn unConcatOutput concatOutput unConcatOutput concatOutput
+
+assertOutputDoesNotContainMultiline :: MonadIO m => WithCallStack (String -> Result -> m ())
+assertOutputDoesNotContainMultiline = assertOutputDoesNotContainOn unConcatOutput concatOutput unConcatOutput concatOutput
 
 assertFindInFile :: MonadIO m => WithCallStack (String -> FilePath -> m ())
 assertFindInFile needle path =
@@ -861,9 +874,29 @@ assertNoFileContains paths needle =
         \path ->
           assertFileDoesNotContain path needle
 
--- | Replace line breaks with spaces, correctly handling "\r\n".
+-- | Replace line breaks with <LF>, correctly handling "\r\n".
 concatOutput :: String -> String
-concatOutput = unwords . lines . filter ((/=) '\r')
+concatOutput =
+    (\s -> if "<LF>" `isPrefixOf` s then drop 4 s else s) .
+    concat . (fmap ("<LF>" ++)) . lines . filter ((/=) '\r')
+
+-- | Replace <LF> markers with line breaks and wrap lines with ^ and $ markers
+-- for the start and end.
+unConcatOutput :: String -> String
+unConcatOutput output =
+    (\xs -> case lines xs of [line0] -> line0 ++ "$"; _ -> xs)
+    . unlines
+    . (fmap ('^' :))
+    . lines
+    . (\s -> if "<LF>" `isPrefixOf` s then drop 4 s else s)
+    $ foldr
+            (\c acc -> c :
+                if ("<LF>" `isPrefixOf` acc)
+                    then "$\n" ++ drop 4 acc
+                    else acc
+            )
+            ""
+    output
 
 -- | The directory where script build artifacts are expected to be cached
 getScriptCacheDirectory :: FilePath -> TestM FilePath
@@ -1093,6 +1126,9 @@ flakyIfCI ticket m = do
 flakyIfWindows :: IssueID -> TestM a -> TestM a
 flakyIfWindows ticket m = flakyIf isWindows ticket m
 
+normalizeWindowsOutput :: String -> String
+normalizeWindowsOutput = if isWindows then map (\x -> case x of '/' -> '\\'; _ -> x) else id
+
 getOpenFilesLimit :: TestM (Maybe Integer)
 #ifdef mingw32_HOST_OS
 -- No MS-specified limit, was determined experimentally on Windows 10 Pro x64,

changelog.d/pr-10646

@@ -0,0 +1,34 @@
+---
+synopsis: Deduplicate path separator duplicates
+packages: [cabal-install-solver]
+prs: 10646
+issues: 10645
+---
+
+The "using configuration from" message no longer has duplicates on Windows when
+the `cabal.project` uses forward slashes for its imports but the message reports
+imports with backslashes.
+
+```diff
+$ cat cabal.project
+import: dir-a/b.config
+
+$ cabal build all --dry-run
+...
+When using configuration from:
+-   - dir-a/b.config
+    - dir-a\b.config
+    - cabal.project
+```
+
+## Ord ProjectConfigPath Instance Changes
+
+For comparison purposes, path separators are normalized to the @buildOS@
+platform's path separator.
+
+```haskell
+-- >>> let abFwd = ProjectConfigPath $ "a/b.config" :| []
+-- >>> let abBwd = ProjectConfigPath $ "a\\b.config" :| []
+-- >>> compare abFwd abBwd
+-- EQ
+```