diff options
Diffstat (limited to 'src/libsyntax')
| -rw-r--r-- | src/libsyntax/source_map.rs | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/src/libsyntax/source_map.rs b/src/libsyntax/source_map.rs index 4e29c77c89e..74cab00d3c1 100644 --- a/src/libsyntax/source_map.rs +++ b/src/libsyntax/source_map.rs @@ -519,7 +519,7 @@ impl SourceMap { /// extract function takes three arguments: a string slice containing the source, an index in /// the slice for the beginning of the span and an index in the slice for the end of the span. fn span_to_source<F>(&self, sp: Span, extract_source: F) -> Result<String, SpanSnippetError> - where F: Fn(&str, usize, usize) -> String + where F: Fn(&str, usize, usize) -> Result<String, SpanSnippetError> { if sp.lo() > sp.hi() { return Err(SpanSnippetError::IllFormedSpan(sp)); @@ -554,9 +554,9 @@ impl SourceMap { } if let Some(ref src) = local_begin.sf.src { - return Ok(extract_source(src, start_index, end_index)); + return extract_source(src, start_index, end_index); } else if let Some(src) = local_begin.sf.external_src.borrow().get_source() { - return Ok(extract_source(src, start_index, end_index)); + return extract_source(src, start_index, end_index); } else { return Err(SpanSnippetError::SourceNotAvailable { filename: local_begin.sf.name.clone() @@ -567,8 +567,9 @@ impl SourceMap { /// Returns the source snippet as `String` corresponding to the given `Span` pub fn span_to_snippet(&self, sp: Span) -> Result<String, SpanSnippetError> { - self.span_to_source(sp, |src, start_index, end_index| src[start_index..end_index] - .to_string()) + self.span_to_source(sp, |src, start_index, end_index| src.get(start_index..end_index) + .map(|s| s.to_string()) + .ok_or_else(|| SpanSnippetError::IllFormedSpan(sp))) } pub fn span_to_margin(&self, sp: Span) -> Option<usize> { @@ -582,7 +583,9 @@ impl SourceMap { /// Returns the source snippet as `String` before the given `Span` pub fn span_to_prev_source(&self, sp: Span) -> Result<String, SpanSnippetError> { - self.span_to_source(sp, |src, start_index, _| src[..start_index].to_string()) + self.span_to_source(sp, |src, start_index, _| src.get(..start_index) + .map(|s| s.to_string()) + .ok_or_else(|| SpanSnippetError::IllFormedSpan(sp))) } /// Extend the given `Span` to just after the previous occurrence of `c`. Return the same span |