1 files changed, 147 insertions, 0 deletions
diff --git a/src/mistune/renderers/rst.py b/src/mistune/renderers/rst.py
new file mode 100644
index 0000000..fa12c21
--- /dev/null
+++ b/src/mistune/renderers/rst.py
@@ -0,0 +1,147 @@
+from typing import Dict, Any
+from textwrap import indent
+from ._list import render_list
+from ..core import BaseRenderer, BlockState
+from ..util import strip_end
+
+
+class RSTRenderer(BaseRenderer):
+    """A renderer for converting Markdown to ReST."""
+    NAME = 'rst'
+
+    #: marker symbols for heading
+    HEADING_MARKERS = {
+      1: '=',
+      2: '-',
+      3: '~',
+      4: '^',
+      5: '"',
+      6: "'",
+    }
+    INLINE_IMAGE_PREFIX = 'img-'
+
+    def iter_tokens(self, tokens, state):
+        prev = None
+        for tok in tokens:
+            # ignore blank line
+            if tok['type'] == 'blank_line':
+                continue
+            tok['prev'] = prev
+            prev = tok
+            yield self.render_token(tok, state)
+
+    def __call__(self, tokens, state: BlockState):
+        state.env['inline_images'] = []
+        out = self.render_tokens(tokens, state)
+        # special handle for line breaks
+        out += '\n\n'.join(self.render_referrences(state)) + '\n'
+        return strip_end(out)
+
+    def render_referrences(self, state: BlockState):
+        images = state.env['inline_images']
+        for index, token in enumerate(images):
+            attrs = token['attrs']
+            alt = self.render_children(token, state)
+            ident = self.INLINE_IMAGE_PREFIX + str(index)
+            yield '.. |' + ident + '| image:: ' + attrs['url'] + '\n   :alt: ' + alt
+
+    def render_children(self, token, state: BlockState):
+        children = token['children']
+        return self.render_tokens(children, state)
+
+    def text(self, token: Dict[str, Any], state: BlockState) -> str:
+        text = token['raw']
+        return text.replace('|', r'\|')
+
+    def emphasis(self, token: Dict[str, Any], state: BlockState) -> str:
+        return '*' + self.render_children(token, state) + '*'
+
+    def strong(self, token: Dict[str, Any], state: BlockState) -> str:
+        return '**' + self.render_children(token, state) + '**'
+
+    def link(self, token: Dict[str, Any], state: BlockState) -> str:
+        attrs = token['attrs']
+        text = self.render_children(token, state)
+        return '`' + text + ' <' + attrs['url'] + '>`__'
+
+    def image(self, token: Dict[str, Any], state: BlockState) -> str:
+        refs: list = state.env['inline_images']
+        index = len(refs)
+        refs.append(token)
+        return '|' + self.INLINE_IMAGE_PREFIX + str(index) + '|'
+
+    def codespan(self, token: Dict[str, Any], state: BlockState) -> str:
+        return '``' + token['raw'] + '``'
+
+    def linebreak(self, token: Dict[str, Any], state: BlockState) -> str:
+        return '<linebreak>'
+
+    def softbreak(self, token: Dict[str, Any], state: BlockState) -> str:
+        return ' '
+
+    def inline_html(self, token: Dict[str, Any], state: BlockState) -> str:
+        # rst does not support inline html
+        return ''
+
+    def paragraph(self, token: Dict[str, Any], state: BlockState) -> str:
+        children = token['children']
+        if len(children) == 1 and children[0]['type'] == 'image':
+            image = children[0]
+            attrs = image['attrs']
+            title = attrs.get('title')
+            alt = self.render_children(image, state)
+            text = '.. figure:: ' + attrs['url']
+            if title:
+                text += '\n   :alt: ' + title
+            text += '\n\n' + indent(alt, '   ')
+        else:
+            text = self.render_tokens(children, state)
+            lines = text.split('<linebreak>')
+            if len(lines) > 1:
+                text = '\n'.join('| ' + line for line in lines)
+        return text + '\n\n'
+
+    def heading(self, token: Dict[str, Any], state: BlockState) -> str:
+        attrs = token['attrs']
+        text = self.render_children(token, state)
+        marker = self.HEADING_MARKERS[attrs['level']]
+        return text + '\n' + marker * len(text) + '\n\n'
+
+    def thematic_break(self, token: Dict[str, Any], state: BlockState) -> str:
+        return '--------------\n\n'
+
+    def block_text(self, token: Dict[str, Any], state: BlockState) -> str:
+        return self.render_children(token, state) + '\n'
+
+    def block_code(self, token: Dict[str, Any], state: BlockState) -> str:
+        attrs = token.get('attrs', {})
+        info = attrs.get('info')
+        code = indent(token['raw'], '   ')
+        if info:
+            lang = info.split()[0]
+            return '.. code:: ' + lang + '\n\n' + code + '\n'
+        else:
+            return '::\n\n' + code + '\n\n'
+
+    def block_quote(self, token: Dict[str, Any], state: BlockState) -> str:
+        text = indent(self.render_children(token, state), '   ')
+        prev = token['prev']
+        ignore_blocks = (
+            'paragraph',
+            'thematic_break',
+            'linebreak',
+            'heading',
+        )
+        if prev and prev['type'] not in ignore_blocks:
+            text = '..\n\n' + text
+        return text
+
+    def block_html(self, token: Dict[str, Any], state: BlockState) -> str:
+        raw = token['raw']
+        return '.. raw:: html\n\n' + indent(raw, '   ') + '\n\n'
+
+    def block_error(self, token: Dict[str, Any], state: BlockState) -> str:
+        return ''
+
+    def list(self, token: Dict[str, Any], state: BlockState) -> str:
+        return render_list(self, token, state)