‼️ BREAKING: Set URL scheme defaults (#329)

Set `myst_url_schemes` default to `("http", "https", "mailto", "ftp")`,
so that only these URL will be considered as external,
and references like `prefix:main` will be considered as internal references.

docs/conf.py

@@ -74,7 +74,6 @@
     "substitution",
     "tasklist",
 ]
-myst_url_schemes = ("http", "https", "mailto")
 myst_heading_anchors = 2
 myst_footnote_transition = True
 myst_dmath_double_inline = True

docs/using/intro.md

@@ -240,7 +240,7 @@ To do so, use the keywords beginning `myst_`.
   - `["dollarmath"]`
   - Enable Markdown extensions, [see here](syntax-optional) for details.
 * - `myst_url_schemes`
-  - `None`
+  - `("http", "https", "mailto", "ftp")`
   - [URI schemes](https://en.wikipedia.org/wiki/List_of_URI_schemes) that will be recognised as external URLs in `[](scheme:loc)` syntax, or set `None` to recognise all.
     Other links will be resolved as internal cross-references.
 * - `myst_heading_anchors`

myst_parser/main.py

@@ -1,4 +1,4 @@
-from typing import Callable, Dict, Iterable, Optional, Tuple, Union
+from typing import Callable, Dict, Iterable, Optional, Tuple, Union, cast
 
 import attr
 from attr.validators import (
@@ -81,7 +81,7 @@ def check_extensions(self, attribute, value):
 
     # see https://en.wikipedia.org/wiki/List_of_URI_schemes
     url_schemes: Optional[Iterable[str]] = attr.ib(
-        default=None,
+        default=cast(Optional[Iterable[str]], ("http", "https", "mailto", "ftp")),
         validator=optional(deep_iterable(instance_of(str), instance_of((list, tuple)))),
     )
 

tests/test_renderers/test_myst_refs.py

@@ -20,6 +20,7 @@
         ("ref", "(ref)=\n# Title\n[](ref)", False),
         ("ref_nested", "(ref)=\n# Title\n[*text*](ref)", False),
         ("duplicate", "(index)=\n# Title\n[](index)", True),
+        ("ref_colon", "(ref:colon)=\n# Title\n[](ref:colon)", False),
     ],
 )
 def test_parse(test_name, text, should_warn, file_regression):

tests/test_renderers/test_myst_refs/ref_colon.xml

@@ -0,0 +1,8 @@
+<document classes="tex2jax_ignore mathjax_ignore" ids="title ref-colon" names="title ref:colon" source="root/index.md" title="Title">
+    <title>
+        Title
+    <target refid="ref-colon">
+    <paragraph>
+        <reference internal="True" refid="ref-colon">
+            <inline classes="std std-ref">
+                Title