From 12a690b4b555086a7a1e0a5429a22dadf6961767 Mon Sep 17 00:00:00 2001
From: Tony Garnock-Jones <tonyg@leastfixedpoint.com>
Date: Tue, 14 Nov 2023 00:49:58 +0100
Subject: [PATCH] Tests for empty line comment, and fix in Rust

---
 implementations/python/tests/samples.pr                  | 6 ++++++
 .../racket/preserves/preserves/tests/samples.pr          | 6 ++++++
 implementations/rust/preserves/src/value/text/reader.rs  | 9 +++++++++
 tests/samples.pr                                         | 6 ++++++
 4 files changed, 27 insertions(+)

diff --git a/implementations/python/tests/samples.pr b/implementations/python/tests/samples.pr
index bd6b456..c55e2aa 100644
--- a/implementations/python/tests/samples.pr
+++ b/implementations/python/tests/samples.pr
@@ -56,6 +56,12 @@
   annotation8a: @"Commas forbidden between @ and annotation in a collection" <ParseError "[@,a b]">
   annotation9: @"Commas forbidden between annotation and underlying" <ParseError "@a, b">
   annotation9a: @"Commas forbidden between annotation and underlying in a collection" <ParseError "[@a, b]">
+  annotation10: @"Line comment that's just hash-newline" <Test #x"85 B100 B000" #
+0>
+  annotation11: @"Line comments: one hash-newline, one normal"
+    <Test #x"85 B100 85 B1066e6f726d616c B000" #
+# normal
+0>
   bytes2: <Test #x"B20568656c6c6f" #"hello">
   bytes2a: <Test @"Internal whitespace is allowed, not including commas" #x"B2 05 68 65 6c 6c 6f" #"hello">
   bytes2b: @"Commas forbidden in internal whitespace" <ParseError "#x\"B2, 05, 68, 65, 6c, 6c, 6f\"">
diff --git a/implementations/racket/preserves/preserves/tests/samples.pr b/implementations/racket/preserves/preserves/tests/samples.pr
index bd6b456..c55e2aa 100644
--- a/implementations/racket/preserves/preserves/tests/samples.pr
+++ b/implementations/racket/preserves/preserves/tests/samples.pr
@@ -56,6 +56,12 @@
   annotation8a: @"Commas forbidden between @ and annotation in a collection" <ParseError "[@,a b]">
   annotation9: @"Commas forbidden between annotation and underlying" <ParseError "@a, b">
   annotation9a: @"Commas forbidden between annotation and underlying in a collection" <ParseError "[@a, b]">
+  annotation10: @"Line comment that's just hash-newline" <Test #x"85 B100 B000" #
+0>
+  annotation11: @"Line comments: one hash-newline, one normal"
+    <Test #x"85 B100 85 B1066e6f726d616c B000" #
+# normal
+0>
   bytes2: <Test #x"B20568656c6c6f" #"hello">
   bytes2a: <Test @"Internal whitespace is allowed, not including commas" #x"B2 05 68 65 6c 6c 6f" #"hello">
   bytes2b: @"Commas forbidden in internal whitespace" <ParseError "#x\"B2, 05, 68, 65, 6c, 6c, 6f\"">
diff --git a/implementations/rust/preserves/src/value/text/reader.rs b/implementations/rust/preserves/src/value/text/reader.rs
index 5f02453..a25ac75 100644
--- a/implementations/rust/preserves/src/value/text/reader.rs
+++ b/implementations/rust/preserves/src/value/text/reader.rs
@@ -520,6 +520,15 @@ impl<'de, 'src, N: NestedValue, Dec: DomainParse<N::Embedded>, S: BinarySource<'
                                 continue 'restart;
                             }
                         }
+                        b'\n' | b'\r' => {
+                            if read_annotations {
+                                let mut annotations = vec![N::new("")];
+                                self.gather_annotations(&mut annotations)?;
+                                self.prepend_annotations_to_next(annotations)?
+                            } else {
+                                continue 'restart;
+                            }
+                        }
                         b'f' => { self.require_delimiter("Delimiter must follow #f")?; N::new(false) }
                         b't' => { self.require_delimiter("Delimiter must follow #t")?; N::new(true) }
                         b'{' => self.read_set(read_annotations)?,
diff --git a/tests/samples.pr b/tests/samples.pr
index bd6b456..c55e2aa 100644
--- a/tests/samples.pr
+++ b/tests/samples.pr
@@ -56,6 +56,12 @@
   annotation8a: @"Commas forbidden between @ and annotation in a collection" <ParseError "[@,a b]">
   annotation9: @"Commas forbidden between annotation and underlying" <ParseError "@a, b">
   annotation9a: @"Commas forbidden between annotation and underlying in a collection" <ParseError "[@a, b]">
+  annotation10: @"Line comment that's just hash-newline" <Test #x"85 B100 B000" #
+0>
+  annotation11: @"Line comments: one hash-newline, one normal"
+    <Test #x"85 B100 85 B1066e6f726d616c B000" #
+# normal
+0>
   bytes2: <Test #x"B20568656c6c6f" #"hello">
   bytes2a: <Test @"Internal whitespace is allowed, not including commas" #x"B2 05 68 65 6c 6c 6f" #"hello">
   bytes2b: @"Commas forbidden in internal whitespace" <ParseError "#x\"B2, 05, 68, 65, 6c, 6c, 6f\"">