futhark literate: do not choke on malformed files.

CHANGELOG.md

@@ -18,6 +18,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ### Fixed
 
+* `futhark literate` no longer fails if the final line is a directive
+  without a trailing newline.
+
 ## [0.25.7]
 
 ### Added

src/Futhark/CLI/Literate.hs

@@ -329,7 +329,7 @@ atStartOfLine = do
   when (col /= pos1) empty
 
 afterExp :: Parser ()
-afterExp = choice [atStartOfLine, void eol]
+afterExp = choice [atStartOfLine, choice [void eol, eof]]
 
 withParsedSource :: Parser a -> (a -> T.Text -> b) -> Parser b
 withParsedSource p f = do
@@ -369,12 +369,12 @@ parseBlock =
             $> DirectiveImg
             <*> parseExp postlexeme
             <*> parseImgParams
-            <* eol,
+            <* choice [void eol, eof],
           directiveName "plot2d"
             $> DirectivePlot
             <*> parseExp postlexeme
             <*> parsePlotParams
-            <* eol,
+            <* choice [void eol, eof],
           directiveName "gnuplot"
             $> DirectiveGnuplot
             <*> parseExp postlexeme
@@ -388,7 +388,7 @@ parseBlock =
             $> DirectiveAudio
             <*> parseExp postlexeme
             <*> parseAudioParams
-            <* eol
+            <* choice [void eol, eof]
         ]
     directiveName s = try $ token (":" <> s)
 

tests_literate/expected/nonl.md

@@ -0,0 +1,14 @@
+Note: it is intentional that this file does not include a final
+newline character. Do not add it!
+
+```futhark
+def main x = x + 1
+```
+
+```
+> main 1
+```
+
+```
+2i32
+```

tests_literate/nonl.fut

@@ -0,0 +1,6 @@
+-- Note: it is intentional that this file does not include a final
+-- newline character. Do not add it!
+
+def main x = x + 1
+
+-- > main 1