More precise blank lines in transcript UCM blocks

This avoids leading and trailing blanks, while ensuring they exist between commands & outputs.

unison-cli-integration/integration-tests/IntegrationTests/transcript.output.md

@@ -2,7 +2,9 @@
 
 ``` ucm :hide
 scratch/main> builtins.mergeio lib.builtins
+
 scratch/main> load ./unison-src/transcripts-using-base/base.u
+
 scratch/main> add
 ```
 
@@ -34,7 +36,6 @@ main = do
 ```
 
 ``` ucm :added-by-ucm
-
   Loading changes detected in scratch.u.
 
   I found and typechecked these definitions in scratch.u. If you
@@ -58,5 +59,6 @@ scratch/main> add
     type MyBool
     main   : '{IO, Exception} ()
     resume : Request {g, Break} x -> x
+
 scratch/main> compile main ./unison-cli-integration/integration-tests/IntegrationTests/main
 ```

unison-cli/src/Unison/Codebase/Transcript/Runner.hs

@@ -176,30 +176,33 @@ run isTest verbosity dir codebase runtime sbRuntime nRuntime ucmVersion baseURL
   let patternMap = Map.fromList $ (\p -> (patternName p, p) : ((,p) <$> aliases p)) =<< validInputs
   let output' :: Bool -> Stanza -> IO ()
       output' inputEcho msg = do
-        hide <- readIORef isHidden
-        unless (hideOutput inputEcho hide) $ modifyIORef' out (<> pure msg)
+        hide <- hideOutput inputEcho
+        unless hide $ modifyIORef' out (<> pure msg)
 
-      hideOutput :: Bool -> Hidden -> Bool
-      hideOutput inputEcho = \case
+      hideOutput' :: Bool -> Hidden -> Bool
+      hideOutput' inputEcho = \case
         Shown -> False
         HideOutput -> not inputEcho
         HideAll -> True
 
+      hideOutput :: Bool -> IO Bool
+      hideOutput inputEcho = hideOutput' inputEcho <$> readIORef isHidden
+
       output, outputEcho :: Stanza -> IO ()
       output = output' False
       outputEcho = output' True
 
       outputUcmLine :: UcmLine -> IO ()
-      outputUcmLine line = modifyIORef' ucmOutput (<> pure line)
+      outputUcmLine line = do
+        prev <- readIORef ucmOutput
+        modifyIORef' ucmOutput (<> ((if not (null prev) then pure (UcmOutputLine "\n") else mempty) <> pure line))
 
       outputUcmResult :: Pretty.Pretty Pretty.ColorText -> IO ()
       outputUcmResult line = do
-        hide <- readIORef isHidden
-        unless (hideOutput False hide) $
+        hide <- hideOutput False
+        unless hide $
           -- We shorten the terminal width, because "Transcript" manages a 2-space indent for output lines.
-          modifyIORef'
-            ucmOutput
-            (<> pure (UcmOutputLine . Text.pack $ Pretty.toPlain (terminalWidth - 2) $ "\n" <> line))
+          outputUcmLine . UcmOutputLine . Text.pack $ Pretty.toPlain (terminalWidth - 2) line
 
       maybeDieWithMsg :: String -> IO ()
       maybeDieWithMsg msg = do
@@ -210,7 +213,7 @@ run isTest verbosity dir codebase runtime sbRuntime nRuntime ucmVersion baseURL
 
       apiRequest :: APIRequest -> IO [APIRequest]
       apiRequest req = do
-        hide <- readIORef isHidden
+        hide <- hideOutput False
         case req of
           -- We just discard this, because the runner will produce new output lines.
           APIResponseLine {} -> pure []
@@ -222,7 +225,7 @@ run isTest verbosity dir codebase runtime sbRuntime nRuntime ucmVersion baseURL
                   (([] <$) . maybeDieWithMsg . (("Error decoding response from " <> Text.unpack path <> ": ") <>))
                   ( \(v :: Aeson.Value) ->
                       pure $
-                        if hide == HideOutput
+                        if hide
                           then [req]
                           else
                             [ req,

unison-src/builtin-tests/interpreter-tests.output.md

@@ -6,7 +6,9 @@ Before merging the PR on Github, we'll merge your branch on Share and restore `r
 
 ``` ucm :hide:error
 scratch/main> this is a hack to trigger an error, in order to swallow any error on the next line.
+
 scratch/main> we delete the project to avoid any merge conflicts or complaints from ucm.
+
 scratch/main> delete.project runtime-tests
 ```
 
@@ -18,6 +20,7 @@ scratch/main> clone @unison/runtime-tests/releases/0.0.1 runtime-tests/selected
 runtime-tests/selected> run tests
 
   ()
+
 runtime-tests/selected> run tests.interpreter.only
 
   ()

unison-src/transcripts-manual/docs.to-html.output.md

@@ -16,7 +16,6 @@ some.outside = 3
 ```
 
 ``` ucm :added-by-ucm
-
   Loading changes detected in scratch.u.
 
   I found and typechecked these definitions in scratch.u. If you
@@ -44,5 +43,6 @@ test-html-docs/main> add
     some.ns.pretty.deeply.nested.doc : Doc2
     some.outside                     : Nat
     some.outside.doc                 : Doc2
+
 test-html-docs/main> docs.to-html some.ns unison-src/transcripts-manual/docs.to-html
 ```

unison-src/transcripts-manual/rewrites.output.md

@@ -1,6 +1,8 @@
 ``` ucm :hide
 scratch/main> builtins.mergeio
+
 scratch/main> load unison-src/transcripts-using-base/base.u
+
 scratch/main> add
 ```
 
@@ -43,6 +45,7 @@ scratch/main> rewrite rule1
   I found and replaced matches in these definitions: ex1
 
   The rewritten file has been added to the top of scratch.u
+
 scratch/main> rewrite eitherToOptional
 
   ☝️
@@ -115,6 +118,7 @@ rule2 x = @rewrite signature Optional ==> Optional2
 
 ``` ucm :hide
 scratch/main> load
+
 scratch/main> add
 ```
 
@@ -202,6 +206,7 @@ blah2 = 456
 
 ``` ucm :hide
 scratch/main> load
+
 scratch/main> add
 ```
 
@@ -239,7 +244,9 @@ sameFileEx =
 
 ``` ucm :hide
 scratch/main> rewrite rule
+
 scratch/main> load
+
 scratch/main> add
 ```
 
@@ -421,6 +428,7 @@ scratch/main> sfind findEitherEx
     1. eitherEx
 
   Tip: Try `edit 1` to bring this into your scratch file.
+
 scratch/main> sfind findEitherFailure
 
   🔎
@@ -435,6 +443,7 @@ scratch/main> sfind findEitherFailure
 
   Tip: Try `edit 1` or `edit 1-5` to bring these into your
        scratch file.
+
 scratch/main> find 1-5
 
   1. Exception.catch : '{g, Exception} a ->{g} Either Failure a

unison-src/transcripts-round-trip/main.output.md

@@ -2,12 +2,15 @@ This transcript verifies that the pretty-printer produces code that can be succe
 
 ``` ucm :hide
 scratch/main> builtins.mergeio lib.builtins
+
 scratch/a1> builtins.mergeio lib.builtins
+
 scratch/a2> builtins.mergeio lib.builtins
 ```
 
 ``` ucm :hide
 scratch/a1> load unison-src/transcripts-round-trip/reparses-with-same-hash.u
+
 scratch/a1> add
 ```
 
@@ -16,7 +19,6 @@ x = ()
 ```
 
 ``` ucm :added-by-ucm
-
   Loading changes detected in scratch.u.
 
   I found and typechecked these definitions in scratch.u. If you
@@ -833,6 +835,7 @@ scratch/a2> load
 
 ``` ucm :hide
 scratch/a2> add
+
 scratch/a2> delete.namespace.force lib.builtins
 ```
 
@@ -848,7 +851,9 @@ Now check that definitions in 'reparses.u' at least parse on round trip:
 
 ``` ucm :hide
 scratch/a3> builtins.mergeio lib.builtins
+
 scratch/a3> load unison-src/transcripts-round-trip/reparses.u
+
 scratch/a3> add
 ```
 
@@ -897,9 +902,13 @@ sloppyDocEval =
 
 ``` ucm :hide
 scratch/a3_new> builtins.mergeio lib.builtins
+
 scratch/a3_new> load
+
 scratch/a3_new> add
+
 scratch/a3> delete.namespace.force lib.builtins
+
 scratch/a3_new> delete.namespace.force lib.builtins
 ```
 
@@ -925,6 +934,7 @@ Regression test for https://github.com/unisonweb/unison/pull/3548
 scratch/regressions> alias.term ##Nat.+ plus
 
   Done.
+
 scratch/regressions> edit.new plus
 
   ☝️
@@ -933,6 +943,7 @@ scratch/regressions> edit.new plus
 
   You can edit them there, then run `update` to replace the
   definitions currently in this namespace.
+
 scratch/regressions> load
 
   Loading changes detected in scratch.u.

unison-src/transcripts-using-base/_base.output.md

@@ -11,7 +11,9 @@ transcripts which contain less boilerplate.
 
 ``` ucm :hide
 scratch/main> builtins.mergeio
+
 scratch/main> load unison-src/transcripts-using-base/base.u
+
 scratch/main> add
 ```
 
@@ -50,7 +52,6 @@ testAutoClean _ =
 ```
 
 ``` ucm :added-by-ucm
-
   Loading changes detected in scratch.u.
 
   I found and typechecked these definitions in scratch.u. If you
@@ -68,6 +69,7 @@ scratch/main> add
   ⍟ I've added these definitions:
 
     testAutoClean : '{IO} [Result]
+
 scratch/main> io.test testAutoClean
 
     New test results:

unison-src/transcripts-using-base/binary-encoding-nats.output.md

@@ -54,7 +54,6 @@ testABunchOfNats _ =
 ```
 
 ``` ucm :added-by-ucm
-
   Loading changes detected in scratch.u.
 
   I found and typechecked these definitions in scratch.u. If you
@@ -90,6 +89,7 @@ scratch/main> add
     testABunchOfNats : ∀ _. _ ->{IO} [Result]
     testNat          : Nat -> '{IO, Stream Result} ()
     testRoundTrip    : Nat -> EncDec ->{IO, Stream Result} ()
+
 scratch/main> io.test testABunchOfNats
 
     New test results:

unison-src/transcripts-using-base/codeops.output.md

@@ -152,7 +152,6 @@ swapped name link =
 ```
 
 ``` ucm :added-by-ucm
-
   Loading changes detected in scratch.u.
 
   I found and typechecked these definitions in scratch.u. If you
@@ -316,7 +315,6 @@ badLoad _ =
 ```
 
 ``` ucm :added-by-ucm
-
   Loading changes detected in scratch.u.
 
   I found and typechecked these definitions in scratch.u. If you
@@ -358,6 +356,7 @@ scratch/main> add
     rotate  : Three Nat Nat Nat -> Three Nat Nat Nat
     tests   : '{IO} [Result]
     zapper  : Three Nat Nat Nat -> Request {Zap} r -> r
+
 scratch/main> io.test tests
 
     New test results:
@@ -379,6 +378,7 @@ scratch/main> io.test tests
   ✅ 13 test(s) passing
 
   Tip: Use view 1 to view the source of a test.
+
 scratch/main> io.test badLoad
 
     New test results:
@@ -427,7 +427,6 @@ codeTests =
 ```
 
 ``` ucm :added-by-ucm
-
   Loading changes detected in scratch.u.
 
   I found and typechecked these definitions in scratch.u. If you
@@ -445,6 +444,7 @@ scratch/main> add
   ⍟ I've added these definitions:
 
     codeTests : '{IO} [Result]
+
 scratch/main> io.test codeTests
 
     New test results:
@@ -512,7 +512,6 @@ vtests _ =
 ```
 
 ``` ucm :added-by-ucm
-
   Loading changes detected in scratch.u.
 
   I found and typechecked these definitions in scratch.u. If you
@@ -532,6 +531,7 @@ scratch/main> add
 
     validateTest : Link.Term ->{IO} Result
     vtests       : '{IO} [Result]
+
 scratch/main> io.test vtests
 
     New test results: