fix(cabal.project parser): parse the packages ending with eof (#222)

CHANGELOG.md

@@ -5,6 +5,7 @@
 - #210: Add `extraLibraries` to `settings` module.
 - #215: Improved debug logging.
 - #216: Remove `debug` option (pass `--trace-verbose` to nix instead)
+- #222: Improve `cabal.project` parser by handling files not ending with newline
 - Breaking changes
   - #221: Switch to `buildFromSdist`, to allow using non-standard package sets (wherein `cabal-install` is otherwise built without using user's overrides)
 

nix/haskell-parsers/parser.nix

@@ -25,7 +25,11 @@ in
       key = parsec.string "packages:\n";
       val =
         parsec.many1
-          (parsec.between spaces1 newline path);
+          (parsec.choice
+            [
+              (parsec.between spaces1 newline path)
+              (parsec.between spaces1 parsec.eof path)
+            ]);
       parser = parsec.skipThen
         key
         val;

nix/haskell-parsers/parser_tests.nix

@@ -17,6 +17,15 @@ let
         '';
         expected = [ "foo" "bar" ];
       };
+
+      # Handles cases where cabal.project does not end with newline
+      testEOF = {
+        expr = eval ''
+          packages:
+            foo
+            bar'';
+        expected = [ "foo" "bar" ];
+      };
     };
   cabalExecutableTests =
     let

test/with-subdir/cabal.project

@@ -1,2 +1,2 @@
 packages:
-  ./haskell-flake-test
+  ./haskell-flake-test