1 files changed, 65 insertions, 0 deletions
diff --git a/docs/users_guide/ghc_packages.py b/docs/users_guide/ghc_packages.py
new file mode 100644
index 0000000000..6419834e1e
--- /dev/null
+++ b/docs/users_guide/ghc_packages.py
@@ -0,0 +1,65 @@
+from docutils import nodes
+from docutils.parsers.rst import Directive, directives
+from sphinx import addnodes
+from sphinx.domains.std import GenericObject
+from sphinx.errors import SphinxError
+from utils import build_table_from_list
+
+def read_cabal_file(pkg_path):
+    import re
+    cabal_file = open(pkg_path, 'r').read()
+    pkg_name = re.search(r'^[nN]ame\s*:\s*([-a-zA-Z0-9]+)', cabal_file, re.MULTILINE)
+    if pkg_name is not None:
+        pkg_name = pkg_name.group(1)
+    else:
+        raise RuntimeError("Failed to parse `Name:` field from %s" % pkg_path)
+
+    pkg_version = re.search(r'^[vV]ersion\s*:\s*(\d+(\.\d+)*)', cabal_file, re.MULTILINE)
+    if pkg_version is not None:
+        pkg_version = pkg_version.group(1)
+    else:
+        raise RuntimeError("Failed to parse `Version:` field from %s" % pkg_path)
+
+    return (pkg_name, pkg_version)
+
+
+class PackageListDirective(Directive):
+    has_content = True
+    def run(self):
+        self.assert_has_content()
+
+        packages = []
+        for line in self.content:
+            (pkg_path, _, reason) = line.partition(':')
+            if len(reason) == 0:
+                raise RuntimeError("Missing reason for inclusion of package %s"
+                                   % pkg_path)
+
+            # Parse reason
+            from docutils.statemachine import ViewList
+            reason_vl = ViewList(initlist=[reason.strip()])
+            reason_node = nodes.paragraph()
+            self.state.nested_parse(reason_vl, 0, reason_node)
+            packages.append((pkg_path, reason_node))
+
+        # Create column headers for table
+        header = [ nodes.inline(text=h)
+                   for h in ["Package", "Version", "Reason for inclusion"] ]
+        package_list = [header]
+
+        for (pkg_path, reason) in sorted(packages):
+            (pkg_name, pkg_version) = read_cabal_file(pkg_path)
+            cells = [ nodes.paragraph(text=pkg_name),
+                      nodes.inline(text=pkg_version),
+                      reason ]
+            package_list.append(cells)
+
+        table = build_table_from_list(package_list, [20, 20, 40])
+        table['classes'].append('longtable')
+        return [table]
+
+### Initialization
+def setup(app):
+    app.add_directive('ghc-package-list', PackageListDirective)
+
+    return {'version': '1.0'}