From 169bf69f5e419703757e758778f58741d8cde602 Mon Sep 17 00:00:00 2001
From: Tom Alexander <tom@fizz.buzz>
Date: Wed, 4 Oct 2023 13:23:57 -0400
Subject: [PATCH] Preserve the leading whitespace before an escape.

---
 src/compare/diff.rs         |  5 ++---
 src/parser/lesser_block.rs  | 43 +++++++++++++++++++++++++++----------
 src/types/lesser_element.rs | 15 +------------
 3 files changed, 35 insertions(+), 28 deletions(-)

diff --git a/src/compare/diff.rs b/src/compare/diff.rs
index 3e2e44d..938622d 100644
--- a/src/compare/diff.rs
+++ b/src/compare/diff.rs
@@ -1549,12 +1549,11 @@ fn compare_example_block<'b, 's>(
 
     // Compare value
     let contents = get_property_quoted_string(emacs, ":value")?.unwrap_or(String::new());
-    let rust_contents = rust.get_contents();
-    if contents != rust_contents {
+    if contents != rust.contents {
         this_status = DiffStatus::Bad;
         message = Some(format!(
             "Value mismatch (emacs != rust) {:?} != {:?}",
-            contents, rust_contents
+            contents, rust.contents
         ));
     }
 
diff --git a/src/parser/lesser_block.rs b/src/parser/lesser_block.rs
index 39a44fa..4886965 100644
--- a/src/parser/lesser_block.rs
+++ b/src/parser/lesser_block.rs
@@ -9,15 +9,12 @@ use nom::character::complete::space1;
 use nom::combinator::consumed;
 use nom::combinator::eof;
 use nom::combinator::map;
-use nom::combinator::not;
 use nom::combinator::opt;
 use nom::combinator::peek;
 use nom::combinator::recognize;
 use nom::combinator::verify;
-use nom::multi::many0;
 use nom::multi::many_till;
 use nom::multi::separated_list1;
-use nom::sequence::preceded;
 use nom::sequence::tuple;
 
 use super::org_source::OrgSource;
@@ -156,10 +153,7 @@ pub(crate) fn example_block<'b, 'g, 'r, 's>(
     let parser_context = parser_context.with_additional_node(&contexts[2]);
     let parameters = parameters.map(|(_, parameters)| parameters);
 
-    let (remaining, contents) = many0(preceded(
-        not(parser_with_context!(exit_matcher_parser)(&parser_context)),
-        map(content_line, Into::<&str>::into),
-    ))(remaining)?;
+    let (remaining, contents) = content(&parser_context, remaining)?;
     let (remaining, _end) = lesser_block_end_specialized(&parser_context, remaining)?;
 
     let source = get_consumed(input, remaining);
@@ -441,8 +435,35 @@ fn switch_word<'s>(input: OrgSource<'s>) -> Res<OrgSource<'s>, OrgSource<'s>> {
 }
 
 #[cfg_attr(feature = "tracing", tracing::instrument(ret, level = "debug"))]
-fn content_line<'s>(input: OrgSource<'s>) -> Res<OrgSource<'s>, OrgSource<'s>> {
-    let (remaining, _) = opt(tuple((space0, tag(","), peek(alt((tag("#+"), tag("*")))))))(input)?;
-    let (remaining, line_post_escape) = recognize(many_till(anychar, line_ending))(remaining)?;
-    Ok((remaining, line_post_escape))
+pub(crate) fn content<'b, 'g, 'r, 's>(
+    context: RefContext<'b, 'g, 'r, 's>,
+    input: OrgSource<'s>,
+) -> Res<OrgSource<'s>, String> {
+    let mut ret = String::new();
+    let mut remaining = input;
+    let exit_matcher_parser = parser_with_context!(exit_matcher_parser)(context);
+    loop {
+        if exit_matcher_parser(remaining).is_ok() {
+            break;
+        }
+
+        let (remain, (pre_escape_whitespace, line)) = content_line(remaining)?;
+        pre_escape_whitespace.map(|val| ret.push_str(Into::<&str>::into(val)));
+        ret.push_str(line.into());
+        remaining = remain;
+    }
+
+    Ok((remaining, ret))
+}
+
+#[cfg_attr(feature = "tracing", tracing::instrument(ret, level = "debug"))]
+fn content_line<'s>(
+    input: OrgSource<'s>,
+) -> Res<OrgSource<'s>, (Option<OrgSource<'s>>, OrgSource<'s>)> {
+    let (remaining, pre_escape_whitespace) = opt(map(
+        tuple((space0, tag(","), peek(alt((tag("#+"), tag("*")))))),
+        |(pre_comma, _, _)| pre_comma,
+    ))(input)?;
+    let (remaining, line_post_escape) = recognize(many_till(anychar, line_ending))(remaining)?;
+    Ok((remaining, (pre_escape_whitespace, line_post_escape)))
 }
diff --git a/src/types/lesser_element.rs b/src/types/lesser_element.rs
index a90c826..5f1f29c 100644
--- a/src/types/lesser_element.rs
+++ b/src/types/lesser_element.rs
@@ -45,7 +45,7 @@ pub struct ExampleBlock<'s> {
     pub retain_labels: bool,
     pub use_labels: bool,
     pub label_format: Option<&'s str>,
-    pub contents: Vec<&'s str>,
+    pub contents: String,
 }
 
 #[derive(Debug)]
@@ -237,16 +237,3 @@ impl<'s> Comment<'s> {
         ret
     }
 }
-
-impl<'s> ExampleBlock<'s> {
-    /// Get the inner contents of the ExampleBlock with the escaping commas removed.
-    pub fn get_contents(&self) -> String {
-        let final_size = self.contents.iter().map(|line| line.len()).sum();
-        let mut ret = String::with_capacity(final_size);
-        for line in &self.contents {
-            ret.push_str(line);
-        }
-
-        ret
-    }
-}