list-depends: Get much more robust with parsing requirements.txt

2 files changed, 80 insertions, 26 deletions

diff --git a/list-depends b/list-depends
index ddcef9e..f248ccb 100755
--- a/list-depends
+++ b/list-depends
@@ -18,29 +18,5 @@
 [[ -n $stat_file ]] || stat_file='depends_static.txt'
 [[ -n $prod_file ]] || prod_file='https://projects.parabolagnulinux.org/parabolaweb.git/plain/requirements_prod.txt'
 
-cat "${stat_file}" |
-sed -r \
-	-e 's/\s*#.*//'
-
-curl -s "${prod_file}" |
-sed -r \
-	-e 's|^-e .*/fredj/cssmin.git@master#egg=cssmin$|python2-cssmin-fredj|' \
-	-e 's/.*/\L&/' \
-	-e 's/^(python2?-)?/python2-/' |
-while read -r dep; do
-	# This one is a little more complicated, because with ==
-	# depends, I don't want to actually lock to that precise of a
-	# version; it would be a nightmare with keeping things in
-	# sync.  So, let's turn == into >=, but also make sure the
-	# first two segments match.
-	if [[ $dep = *==* ]]; then
-		name="${dep%%==*}"
-		ver="${dep#*==}"
-		IFS=.
-		read major minor patch <<<"$ver"
-		echo "$name>=$ver"
-		echo "$name<$major.$((minor+1))"
-	else
-		echo "$dep"
-	fi
-done
+sed -r -e 's/\s*#.*//' <"${stat_file}"
+"$(dirname -- "$0")/pip2pacman" "${prod_file}"
diff --git a/pip2pacman b/pip2pacman
new file mode 100755
index 0000000..ff1975b
--- /dev/null
+++ b/pip2pacman
@@ -0,0 +1,78 @@
+#!/usr/bin/env python
+
+#   Copyright (c) 2013, 2015, 2019 Luke Shumaker <lukeshu@parabola.nu>
+#
+#   This program is free software; you can redistribute it and/or modify
+#   it under the terms of the GNU General Public License as published by
+#   the Free Software Foundation; either version 2 of the License, or
+#   (at your option) any later version.
+#
+#   This program is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#   GNU General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import re
+
+from pip._internal.req import parse_requirements
+from pip._internal.download import PipSession
+from packaging.specifiers import Specifier
+
+vcspkgs = {
+    'git+git://github.com/fredj/cssmin.git@master#egg=cssmin': 'python2-cssmin-fredj',
+}
+
+
+def nextver(ver):
+    parts = re.sub(r"(a|b|rc|\.dev|\.post|\+).*", '', ver).split('.')
+    parts.pop()
+    parts += [str(int(parts.pop())+1)]
+    return '.'.join(parts)
+
+
+# https://pip.pypa.io/en/stable/reference/pip_install/#requirements-file-format
+# https://setuptools.readthedocs.io/en/latest/pkg_resources.html#requirements-parsing
+# https://www.python.org/dev/peps/pep-0440/
+def main(args):
+    for filename in args:
+        for req in parse_requirements(filename, session=PipSession()):
+            depname = re.sub(r"^(python2?-)?", 'python2-', req.name.lower())
+            if req.link:
+                if req.link.url not in vcspkgs:
+                    raise f"no known package for VCS dep {req}"
+                depname = vcspkgs[req.link.url]
+            if req.specifier:
+                for spec in req.specifier:
+                    # Hack: Allow some slop with '==', otherwise it would be a
+                    # nightmare with keeping things in sync.
+                    if spec.operator == "==":
+                        if len(spec.version.split('.')) <= 2:
+                                spec = Specifier(f"=={spec.version}.*")
+                        else:
+                                spec = Specifier(f"~={spec.version}")
+
+                    if spec.operator == "~=":
+                        print(f"{depname}>={spec.version} {depname}<{nextver(spec.version)}")
+                    elif spec.operator == "==":
+                        if spec.version.endswith(".*"):
+                            print(f"{depname}>={spec.version[:-2]} {depname}<{nextver(spec.version)}")
+                        else:
+                            print(f"{depname}={spec.version}")
+                    elif spec.operator == '!=':
+                        raise f"version exclusion is not supported: {req}"
+                    elif spec.operator in {'<=', '>=', '<', '>'}:
+                        print(f"{depname}{spec.operator}{spec.version}")
+                    elif spec.operator == "===":
+                        print(f"{depname}={spec.version}")
+                    else:
+                        raise f"unknown specifier operator: {spec.operator}: {req}"
+            else:
+                print(f"{depname}")
+
+
+if __name__ == '__main__':
+    import sys
+    main(sys.argv[1:])