diff options
Diffstat (limited to 'components/layout/fragment.rs')
| -rw-r--r-- | components/layout/fragment.rs | 147 |
1 files changed, 127 insertions, 20 deletions
diff --git a/components/layout/fragment.rs b/components/layout/fragment.rs index 281eeaaa5d2..2b802c43cdd 100644 --- a/components/layout/fragment.rs +++ b/components/layout/fragment.rs @@ -598,9 +598,10 @@ pub struct SplitInfo { impl SplitInfo { fn new(range: Range<CharIndex>, info: &ScannedTextFragmentInfo) -> SplitInfo { + let inline_size = info.run.advance_for_range(&range); SplitInfo { range: range, - inline_size: info.run.advance_for_range(&range), + inline_size: inline_size, } } } @@ -1169,7 +1170,9 @@ impl Fragment { pub fn inline_start_offset(&self) -> Au { match self.specific { SpecificFragmentInfo::TableWrapper => self.margin.inline_start, - SpecificFragmentInfo::Table | SpecificFragmentInfo::TableCell | SpecificFragmentInfo::TableRow => self.border_padding.inline_start, + SpecificFragmentInfo::Table | + SpecificFragmentInfo::TableCell | + SpecificFragmentInfo::TableRow => self.border_padding.inline_start, SpecificFragmentInfo::TableColumn(_) => Au(0), _ => self.margin.inline_start + self.border_padding.inline_start, } @@ -1208,9 +1211,12 @@ impl Fragment { pub fn compute_intrinsic_inline_sizes(&mut self) -> IntrinsicISizesContribution { let mut result = self.style_specified_intrinsic_inline_size(); match self.specific { - SpecificFragmentInfo::Generic | SpecificFragmentInfo::Iframe(_) | - SpecificFragmentInfo::Table | SpecificFragmentInfo::TableCell | - SpecificFragmentInfo::TableColumn(_) | SpecificFragmentInfo::TableRow | + SpecificFragmentInfo::Generic | + SpecificFragmentInfo::Iframe(_) | + SpecificFragmentInfo::Table | + SpecificFragmentInfo::TableCell | + SpecificFragmentInfo::TableColumn(_) | + SpecificFragmentInfo::TableRow | SpecificFragmentInfo::TableWrapper | SpecificFragmentInfo::InlineAbsoluteHypothetical(_) => {} SpecificFragmentInfo::InlineBlock(ref mut info) => { @@ -1274,8 +1280,13 @@ impl Fragment { /// TODO: What exactly does this function return? Why is it Au(0) for SpecificFragmentInfo::Generic? pub fn content_inline_size(&self) -> Au { match self.specific { - SpecificFragmentInfo::Generic | SpecificFragmentInfo::Iframe(_) | SpecificFragmentInfo::Table | SpecificFragmentInfo::TableCell | - SpecificFragmentInfo::TableRow | SpecificFragmentInfo::TableWrapper | SpecificFragmentInfo::InlineBlock(_) | + SpecificFragmentInfo::Generic | + SpecificFragmentInfo::Iframe(_) | + SpecificFragmentInfo::Table | + SpecificFragmentInfo::TableCell | + SpecificFragmentInfo::TableRow | + SpecificFragmentInfo::TableWrapper | + SpecificFragmentInfo::InlineBlock(_) | SpecificFragmentInfo::InlineAbsoluteHypothetical(_) => Au(0), SpecificFragmentInfo::Canvas(ref canvas_fragment_info) => { canvas_fragment_info.replaced_image_fragment_info.computed_inline_size() @@ -1288,16 +1299,25 @@ impl Fragment { let text_bounds = run.metrics_for_range(range).bounding_box; text_bounds.size.width } - SpecificFragmentInfo::TableColumn(_) => panic!("Table column fragments do not have inline_size"), - SpecificFragmentInfo::UnscannedText(_) => panic!("Unscanned text fragments should have been scanned by now!"), + SpecificFragmentInfo::TableColumn(_) => { + panic!("Table column fragments do not have inline_size") + } + SpecificFragmentInfo::UnscannedText(_) => { + panic!("Unscanned text fragments should have been scanned by now!") + } } } /// Returns, and computes, the block-size of this fragment. pub fn content_block_size(&self, layout_context: &LayoutContext) -> Au { match self.specific { - SpecificFragmentInfo::Generic | SpecificFragmentInfo::Iframe(_) | SpecificFragmentInfo::Table | SpecificFragmentInfo::TableCell | - SpecificFragmentInfo::TableRow | SpecificFragmentInfo::TableWrapper | SpecificFragmentInfo::InlineBlock(_) | + SpecificFragmentInfo::Generic | + SpecificFragmentInfo::Iframe(_) | + SpecificFragmentInfo::Table | + SpecificFragmentInfo::TableCell | + SpecificFragmentInfo::TableRow | + SpecificFragmentInfo::TableWrapper | + SpecificFragmentInfo::InlineBlock(_) | SpecificFragmentInfo::InlineAbsoluteHypothetical(_) => Au(0), SpecificFragmentInfo::Image(ref image_fragment_info) => { image_fragment_info.replaced_image_fragment_info.computed_block_size() @@ -1309,8 +1329,12 @@ impl Fragment { // Compute the block-size based on the line-block-size and font size. self.calculate_line_height(layout_context) } - SpecificFragmentInfo::TableColumn(_) => panic!("Table column fragments do not have block_size"), - SpecificFragmentInfo::UnscannedText(_) => panic!("Unscanned text fragments should have been scanned by now!"), + SpecificFragmentInfo::TableColumn(_) => { + panic!("Table column fragments do not have block_size") + } + SpecificFragmentInfo::UnscannedText(_) => { + panic!("Unscanned text fragments should have been scanned by now!") + } } } @@ -1463,7 +1487,8 @@ impl Fragment { max_inline_size: Au, flags: SplitOptions) -> Option<SplitResult> - where I: Iterator<Item=TextRunSlice<'a>> { + where I: Iterator<Item= + TextRunSlice<'a>> { let text_fragment_info = if let SpecificFragmentInfo::ScannedText(ref text_fragment_info) = self.specific { text_fragment_info @@ -1475,6 +1500,7 @@ impl Fragment { let mut remaining_inline_size = max_inline_size; let mut inline_start_range = Range::new(text_fragment_info.range.begin(), CharIndex(0)); let mut inline_end_range = None; + let mut overflowing = false; debug!("calculate_split_position: splitting text fragment (strlen={}, range={:?}, \ max_inline_size={:?})", @@ -1508,12 +1534,23 @@ impl Fragment { continue } - // The advance is more than the remaining inline-size, so split here. - let slice_begin = slice.text_run_range().begin(); + // The advance is more than the remaining inline-size, so split here. First, check to + // see if we're going to overflow the line. If so, perform a best-effort split. + let mut remaining_range = slice.text_run_range(); + if inline_start_range.is_empty() { + // We're going to overflow the line. + overflowing = true; + inline_start_range = slice.text_run_range(); + remaining_range = Range::new(slice.text_run_range().end(), CharIndex(0)); + remaining_range.extend_to(text_fragment_info.range.end()); + } + + // Check to see if we need to create an inline-end chunk. + let slice_begin = remaining_range.begin(); if slice_begin < text_fragment_info.range.end() { // There still some things left over at the end of the line, so create the // inline-end chunk. - let mut inline_end = slice.text_run_range(); + let mut inline_end = remaining_range; inline_end.extend_to(text_fragment_info.range.end()); inline_end_range = Some(inline_end); debug!("calculate_split_position: splitting remainder with inline-end range={:?}", @@ -1525,8 +1562,7 @@ impl Fragment { } // If we failed to find a suitable split point, we're on the verge of overflowing the line. - let inline_start_is_some = inline_start_range.length() > CharIndex(0); - if pieces_processed_count == 1 || !inline_start_is_some { + if inline_start_range.is_empty() || overflowing { // If we've been instructed to retry at character boundaries (probably via // `overflow-wrap: break-word`), do so. if flags.contains(RETRY_AT_CHARACTER_BOUNDARIES) { @@ -1547,7 +1583,38 @@ impl Fragment { } } - let inline_start = if inline_start_is_some { + // Remove trailing whitespace from the inline-start split, if necessary. + // + // FIXME(pcwalton): Is there a more clever (i.e. faster) way to do this? + strip_trailing_whitespace(&**text_fragment_info.run, &mut inline_start_range); + + // Remove leading whitespace from the inline-end split, if necessary. + // + // FIXME(pcwalton): Is there a more clever (i.e. faster) way to do this? + if let Some(ref mut inline_end_range) = inline_end_range { + let inline_end_fragment_text = + text_fragment_info.run.text.slice_chars(inline_end_range.begin().to_uint(), + inline_end_range.end().to_uint()); + let mut leading_whitespace_character_count = 0i; + for ch in inline_end_fragment_text.chars() { + if ch.is_whitespace() { + leading_whitespace_character_count += 1 + } else { + break + } + } + inline_end_range.adjust_by(CharIndex(leading_whitespace_character_count), + -CharIndex(leading_whitespace_character_count)); + } + + // Normalize our split so that the inline-end fragment will never be `Some` while the + // inline-start fragment is `None`. + if inline_start_range.is_empty() && inline_end_range.is_some() { + inline_start_range = inline_end_range.unwrap(); + inline_end_range = None + } + + let inline_start = if !inline_start_range.is_empty() { Some(SplitInfo::new(inline_start_range, &**text_fragment_info)) } else { None @@ -1563,6 +1630,24 @@ impl Fragment { }) } + /// Attempts to strip trailing whitespace from this fragment by adjusting the text run range. + /// Returns true if any modifications were made. + pub fn strip_trailing_whitespace_if_necessary(&mut self) -> bool { + let text_fragment_info = + if let SpecificFragmentInfo::ScannedText(ref mut text_fragment_info) = self.specific { + text_fragment_info + } else { + return false + }; + + let run = text_fragment_info.run.clone(); + if strip_trailing_whitespace(&**run, &mut text_fragment_info.range) { + self.border_box.size.inline = run.advance_for_range(&text_fragment_info.range); + return true + } + false + } + /// Returns true if this fragment is an unscanned text fragment that consists entirely of /// whitespace that should be stripped. pub fn is_ignorable_whitespace(&self) -> bool { @@ -1982,3 +2067,25 @@ pub enum CoordinateSystem { Self, } +/// Given a range and a text run, adjusts the range to eliminate trailing whitespace. Returns true +/// if any modifications were made. +fn strip_trailing_whitespace(text_run: &TextRun, range: &mut Range<CharIndex>) -> bool { + // FIXME(pcwalton): Is there a more clever (i.e. faster) way to do this? + let text = text_run.text.slice_chars(range.begin().to_uint(), range.end().to_uint()); + let mut trailing_whitespace_character_count = 0i; + for ch in text.chars().rev() { + if ch.is_whitespace() { + trailing_whitespace_character_count += 1 + } else { + break + } + } + + if trailing_whitespace_character_count == 0 { + return false + } + + range.extend_by(-CharIndex(trailing_whitespace_character_count)); + return true +} + |