Allow whitespace in target selectors (backport #10032)

cabal-install/src/Distribution/Client/ScriptUtils.hs

@@ -300,9 +300,9 @@ withContextAndSelectors noTargets kind flags@NixStyleFlags{..} targetStrings glo
         (withGlobalConfig verbosity globalConfigFlag $ withoutProject mkTmpDir)
 
     (tc', ctx', sels) <- case targetStrings of
-      -- Only script targets may contain spaces and or end with ':'.
+      -- Only script targets may end with ':'.
       -- Trying to readTargetSelectors such a target leads to a parse error.
-      [target] | any (\c -> isSpace c) target || ":" `isSuffixOf` target -> do
+      [target] | ":" `isSuffixOf` target -> do
         scriptOrError target [TargetSelectorNoScript $ TargetString1 target]
       _ -> do
         -- In the case where a selector is both a valid target and script, assume it is a target,

cabal-install/src/Distribution/Client/TargetSelector.hs

@@ -327,21 +327,21 @@ parseTargetString =
     parseTargetApprox :: Parse.ReadP r TargetString
     parseTargetApprox =
       ( do
-          a <- tokenQ
+          a <- tokenQEnd
           return (TargetString1 a)
       )
         +++ ( do
                 a <- tokenQ0
                 _ <- Parse.char ':'
-                b <- tokenQ
+                b <- tokenQEnd
                 return (TargetString2 a b)
             )
         +++ ( do
                 a <- tokenQ0
                 _ <- Parse.char ':'
                 b <- tokenQ
                 _ <- Parse.char ':'
-                c <- tokenQ
+                c <- tokenQEnd
                 return (TargetString3 a b c)
             )
         +++ ( do
@@ -351,7 +351,7 @@ parseTargetString =
                 _ <- Parse.char ':'
                 c <- tokenQ
                 _ <- Parse.char ':'
-                d <- tokenQ
+                d <- tokenQEnd
                 return (TargetString4 a b c d)
             )
         +++ ( do
@@ -363,7 +363,7 @@ parseTargetString =
                 _ <- Parse.char ':'
                 d <- tokenQ
                 _ <- Parse.char ':'
-                e <- tokenQ
+                e <- tokenQEnd
                 return (TargetString5 a b c d e)
             )
         +++ ( do
@@ -379,14 +379,16 @@ parseTargetString =
                 _ <- Parse.char ':'
                 f <- tokenQ
                 _ <- Parse.char ':'
-                g <- tokenQ
+                g <- tokenQEnd
                 return (TargetString7 a b c d e f g)
             )
 
     token = Parse.munch1 (\x -> not (isSpace x) && x /= ':')
     tokenQ = parseHaskellString <++ token
     token0 = Parse.munch (\x -> not (isSpace x) && x /= ':')
     tokenQ0 = parseHaskellString <++ token0
+    tokenEnd = Parse.munch1 (/= ':')
+    tokenQEnd = parseHaskellString <++ tokenEnd
     parseHaskellString :: Parse.ReadP r String
     parseHaskellString = Parse.readS_to_P reads
 

cabal-install/tests/IntegrationTests2.hs

@@ -260,11 +260,14 @@ testTargetSelectors reportSubCase = do
                                   ":pkg:q:lib:q:file:Q.y"
                      , "app/Main.hs", "p:app/Main.hs", "exe:ppexe:app/Main.hs", "p:ppexe:app/Main.hs",
                                   ":pkg:p:exe:ppexe:file:app/Main.hs"
+                     , "a p p/Main.hs", "p:a p p/Main.hs", "exe:pppexe:a p p/Main.hs", "p:pppexe:a p p/Main.hs",
+                                  ":pkg:p:exe:pppexe:file:a p p/Main.hs"
                      ]
        ts @?= replicate 5 (TargetComponent "p-0.1" (CLibName LMainLibName) (FileTarget "P"))
            ++ replicate 5 (TargetComponent "q-0.1" (CLibName LMainLibName) (FileTarget "QQ"))
            ++ replicate 5 (TargetComponent "q-0.1" (CLibName LMainLibName) (FileTarget "Q"))
            ++ replicate 5 (TargetComponent "p-0.1" (CExeName "ppexe") (FileTarget ("app" </> "Main.hs")))
+           ++ replicate 5 (TargetComponent "p-0.1" (CExeName "pppexe") (FileTarget ("a p p" </> "Main.hs")))
        -- Note there's a bit of an inconsistency here: for the single-part
        -- syntax the target has to point to a file that exists, whereas for
        -- all the other forms we don't require that.
@@ -278,9 +281,8 @@ testTargetSelectors reportSubCase = do
 testTargetSelectorBadSyntax :: Assertion
 testTargetSelectorBadSyntax = do
     (_, _, _, localPackages, _) <- configureProject testdir config
-    let targets = [ "foo bar",  " foo"
-                  , "foo:", "foo::bar"
-                  , "foo: ", "foo: :bar"
+    let targets = [ "foo:", "foo::bar"
+                  , " :foo", "foo: :bar"
                   , "a:b:c:d:e:f", "a:b:c:d:e:f:g:h" ]
     Left errs <- readTargetSelectors localPackages Nothing targets
     zipWithM_ (@?=) errs (map TargetSelectorUnrecognised targets)

cabal-install/tests/IntegrationTests2/targets/simple/p.cabal

@@ -15,3 +15,8 @@ executable ppexe
   main-is: Main.hs
   hs-source-dirs: app
   other-modules: PMain
+
+executable pppexe
+  main-is: Main.hs
+  hs-source-dirs: "a p p"
+  other-modules: PMain

cabal-testsuite/PackageTests/NewBuild/T8875/T8875.cabal

@@ -0,0 +1,9 @@
+cabal-version: 3.0
+name: T8875
+version: 0.1.0.0
+
+executable foo
+    main-is: Main.hs
+    build-depends: base
+    hs-source-dirs: "a app"
+    default-language: Haskell2010

cabal-testsuite/PackageTests/NewBuild/T8875/a app/Main.hs

@@ -0,0 +1 @@
+main = return ()

cabal-testsuite/PackageTests/NewBuild/T8875/cabal.out

@@ -0,0 +1,8 @@
+# cabal v2-build
+Resolving dependencies...
+Build profile: -w ghc-<GHCVER> -O1
+In order, the following will be built:
+ - T8875-0.1.0.0 (exe:foo) (first run)
+Configuring executable 'foo' for T8875-0.1.0.0...
+Preprocessing executable 'foo' for T8875-0.1.0.0...
+Building executable 'foo' for T8875-0.1.0.0...

cabal-testsuite/PackageTests/NewBuild/T8875/cabal.project

@@ -0,0 +1 @@
+packages: .

cabal-testsuite/PackageTests/NewBuild/T8875/cabal.test.hs

@@ -0,0 +1,5 @@
+import Test.Cabal.Prelude
+
+main = cabalTest . void $ do
+    -- Building a target that contains whitespace
+    cabal' "v2-build" ["a app/Main.hs"]

changelog.d/issue-8875

@@ -0,0 +1,10 @@
+synopsis: Allow whitespace in targets
+packages: cabal-install
+prs: #10032
+issues: #8875
+
+description: {
+Allow spaces in the final component of target selectors. This resolves an issue
+where using absolute paths in selectors can fail if there is whitespace in the
+parent directories of the project.
+}