build: replace changelog-d with local script

hacking changelog-d to support not just github but also forgejo and
gerrit is a lot more complicated than it's worth, even moreso since
the entire thing can just as well be done with ~60 lines of python.
this new script is also much cheaper to instantiate (being python),
so having it enabled in all shells is far less of a hassle.

we've also adjusted existing release notes that referenced a gerrit
cl to auto-link to the cl in question, making the diff a bit bigger

closes https://git.lix.systems/lix-project/lix/issues/176

Change-Id: I8ba7dd0070aad9ba4474401731215fcf5d9d2130

14 files changed, 85 insertions, 79 deletions

diff --git a/doc/manual/local.mk b/doc/manual/local.mk
index b9e7b8398..b33a4f777 100644
--- a/doc/manual/local.mk
+++ b/doc/manual/local.mk
@@ -151,9 +151,9 @@ $(d)/language.json: $(doc_nix)
 
 # Generate "Upcoming release" notes (or clear it and remove from menu)
 $(d)/src/release-notes/rl-next.md: $(d)/rl-next $(d)/rl-next/*
-	@if type -p changelog-d > /dev/null; then \
+	@if type -p build-release-notes > /dev/null; then \
 		echo "  GEN   " $@; \
-		changelog-d doc/manual/rl-next > $@; \
+		build-release-notes doc/manual/rl-next > $@; \
 	else \
 		echo "  NULL  " $@; \
 		true > $@; \
diff --git a/doc/manual/rl-next/config b/doc/manual/rl-next/config
deleted file mode 100644
index b3c2e868f..000000000
--- a/doc/manual/rl-next/config
+++ /dev/null
@@ -1,2 +0,0 @@
-organization: NixOS
-repository: nix
diff --git a/doc/manual/rl-next/dup-attr-errors.md b/doc/manual/rl-next/dup-attr-errors.md
index 127c8ceb1..cce3d9f30 100644
--- a/doc/manual/rl-next/dup-attr-errors.md
+++ b/doc/manual/rl-next/dup-attr-errors.md
@@ -1,6 +1,6 @@
 ---
 synopsis: Duplicate attribute reports are more accurate
-# prs: cl 557
+cls: 557
 ---
 
 Duplicate attribute errors are now more accurate, showing the path at which an error was detected rather than the full, possibly longer, path that caused the error.
diff --git a/doc/manual/rl-next/nixversion-fake.md b/doc/manual/rl-next/nixversion-fake.md
index 1a97e412c..6e42b2bd2 100644
--- a/doc/manual/rl-next/nixversion-fake.md
+++ b/doc/manual/rl-next/nixversion-fake.md
@@ -1,6 +1,6 @@
 ---
 synopsis: "`builtins.nixVersion` now returns a fixed value \"2.18.3-lix\""
-# prs: cl 558
+cls: 558
 ---
 
 `builtins.nixVersion` now returns a fixed value `"2.18.3-lix"`. This prevents
diff --git a/doc/manual/rl-next/short-expr-flag.md b/doc/manual/rl-next/short-expr-flag.md
index a02c944bd..5fddd3a25 100644
--- a/doc/manual/rl-next/short-expr-flag.md
+++ b/doc/manual/rl-next/short-expr-flag.md
@@ -1,6 +1,6 @@
 ---
 synopsis: reintroduce shortened `-E` form for `--expr` to new CLI
-# prs: cl 605
+cls: 605
 ---
 
 In the past, it was possible to supply a shorter `-E` flag instead of fully
diff --git a/doc/manual/rl-next/upstart-removal.md b/doc/manual/rl-next/upstart-removal.md
index faec2264a..b1b7ad176 100644
--- a/doc/manual/rl-next/upstart-removal.md
+++ b/doc/manual/rl-next/upstart-removal.md
@@ -1,6 +1,6 @@
 ---
 synopsis: Upstart scripts removed
-# prs: cl 574
+cls: 574
 ---
 
 Upstart scripts have been removed from Lix, since Upstart is obsolete and has
diff --git a/doc/manual/src/contributing/hacking.md b/doc/manual/src/contributing/hacking.md
index 3693361bb..133a61b5c 100644
--- a/doc/manual/src/contributing/hacking.md
+++ b/doc/manual/src/contributing/hacking.md
@@ -340,9 +340,6 @@ Significant changes should add the following header, which moves them to the top
 significance: significant
 ```
 
-<!-- Keep an eye on https://codeberg.org/fgaz/changelog-d/issues/1 -->
-See also the [format documentation](https://github.com/haskell/cabal/blob/master/CONTRIBUTING.md#changelog).
-
 ### Build process
 
 Releases have a precomputed `rl-MAJOR.MINOR.md`, and no `rl-next.md`.
diff --git a/flake.nix b/flake.nix
index 21d6de9e8..eab714f99 100644
--- a/flake.nix
+++ b/flake.nix
@@ -150,7 +150,8 @@
           # Forward from the previous stage as we don’t want it to pick the lowdown override
           nixUnstable = prev.nixUnstable;
 
-          changelog-d = final.buildPackages.callPackage ./misc/changelog-d.nix { };
+          build-release-notes =
+            final.buildPackages.callPackage ./maintainers/build-release-notes.nix { };
           boehmgc-nix = (final.boehmgc.override {
             enableLargeConfig = true;
           }).overrideAttrs (o: {
@@ -238,7 +239,7 @@
 
           nix = pkgs.callPackage ./package.nix {
             inherit versionSuffix fileset officialRelease buildUnreleasedNotes;
-            inherit (pkgs) changelog-d;
+            inherit (pkgs) build-release-notes;
             internalApiDocs = true;
             boehmgc = pkgs.boehmgc-nix;
             busybox-sandbox-shell = pkgs.busybox-sandbox-shell;
@@ -288,7 +289,7 @@
         rl-next =
           let pkgs = nixpkgsFor.${system}.native;
           in pkgs.buildPackages.runCommand "test-rl-next-release-notes" { } ''
-          LANG=C.UTF-8 ${pkgs.changelog-d}/bin/changelog-d ${./doc/manual/rl-next} >$out
+          LANG=C.UTF-8 ${lib.getExe pkgs.build-release-notes} ${./doc/manual/rl-next} >$out
         '';
       } // (lib.optionalAttrs (builtins.elem system linux64BitSystems)) {
         dockerImage = self.hydraJobs.dockerImage.${system};
diff --git a/maintainers/build-release-notes.nix b/maintainers/build-release-notes.nix
new file mode 100644
index 000000000..9462e33d7
--- /dev/null
+++ b/maintainers/build-release-notes.nix
@@ -0,0 +1,6 @@
+{ lib, python3, writeShellScriptBin }:
+
+writeShellScriptBin "build-release-notes" ''
+  exec ${lib.getExe (python3.withPackages (p: [ p.python-frontmatter ]))} \
+    ${./build-release-notes.py} "$@"
+''
diff --git a/maintainers/build-release-notes.py b/maintainers/build-release-notes.py
new file mode 100755
index 000000000..ba645d19a
--- /dev/null
+++ b/maintainers/build-release-notes.py
@@ -0,0 +1,66 @@
+import frontmatter
+import sys
+import pathlib
+import textwrap
+
+GH_BASE = "https://github.com/NixOS/nix"
+FORGEJO_BASE = "https://git.lix.systems/lix-project/lix"
+GERRIT_BASE = "https://gerrit.lix.systems/c/lix/+"
+
+SIGNIFICANCECES = {
+    None: 0,
+    'significant': 10,
+}
+
+def format_link(ident: str, gh_part: str, fj_part: str) -> str:
+    # FIXME: deprecate github as default
+    if ident.isdigit():
+        num, link, base = int(ident), f"#{ident}", f"{GH_BASE}/{gh_part}"
+    elif ident.startswith("gh#"):
+        num, link, base = int(ident[3:]), ident, f"{GH_BASE}/{gh_part}"
+    elif ident.startswith("fj#"):
+        num, link, base = int(ident[3:]), ident, f"{FORGEJO_BASE}/{fj_part}"
+    else:
+        raise Exception("unrecognized reference format", ident)
+    return f"[{link}]({base}/{num})"
+
+def format_issue(issue: str) -> str:
+    return format_link(issue, "issues", "issues")
+def format_pr(pr: str) -> str:
+    return format_link(pr, "pull", "pulls")
+def format_cl(cl: str) -> str:
+    clid = int(cl)
+    return f"[cl/{clid}]({GERRIT_BASE}/{clid})"
+
+paths = pathlib.Path(sys.argv[1]).glob('*.md')
+entries = []
+for p in paths:
+    try:
+        e = frontmatter.load(p)
+        if 'synopsis' not in e.metadata:
+            raise Exception('missing synposis')
+        unknownKeys = set(e.metadata.keys()) - set(('synopsis', 'cls', 'issues', 'prs', 'significance'))
+        if unknownKeys:
+            raise Exception('unknown keys', unknownKeys)
+        entries.append((p, e))
+    except Exception as e:
+        e.add_note(f"in {p}")
+        raise
+
+for p, entry in sorted(entries, key=lambda e: (-SIGNIFICANCECES[e[1].metadata.get('significance')], e[0])):
+    try:
+        header = entry.metadata['synopsis']
+        links = []
+        links += map(format_issue, str(entry.metadata.get('issues', "")).split())
+        links += map(format_pr, str(entry.metadata.get('prs', "")).split())
+        links += map(format_cl, str(entry.metadata.get('cls', "")).split())
+        if links != []:
+            header += " " + " ".join(links)
+        if header:
+            print(f"- {header}")
+            print()
+        print(textwrap.indent(entry.content, '  '))
+        print()
+    except Exception as e:
+        e.add_note(f"in {p}")
+        raise
diff --git a/maintainers/release-notes b/maintainers/release-notes
index 34cd85a56..c7a4e5074 100755
--- a/maintainers/release-notes
+++ b/maintainers/release-notes
@@ -152,7 +152,7 @@ section_title="Release $version_full ($DATE)"
   # TODO add minor number, and append?
   echo "# $section_title"
   echo
-  changelog-d doc/manual/rl-next | sed -e 's/ *$//'
+  build-release-notes doc/manual/rl-next
 ) | tee -a $file
 
 log "Wrote $file"
diff --git a/misc/changelog-d.cabal.nix b/misc/changelog-d.cabal.nix
deleted file mode 100644
index 76f9353cd..000000000
--- a/misc/changelog-d.cabal.nix
+++ /dev/null
@@ -1,31 +0,0 @@
-{ mkDerivation, aeson, base, bytestring, cabal-install-parsers
-, Cabal-syntax, containers, directory, filepath, frontmatter
-, generic-lens-lite, lib, mtl, optparse-applicative, parsec, pretty
-, regex-applicative, text, pkgs
-}:
-let rev = "f30f6969e9cd8b56242309639d58acea21c99d06";
-in
-mkDerivation {
-  pname = "changelog-d";
-  version = "0.1";
-  src = pkgs.fetchurl {
-    name = "changelog-d-${rev}.tar.gz";
-    url = "https://codeberg.org/roberth/changelog-d/archive/${rev}.tar.gz";
-    hash = "sha256-8a2+i5u7YoszAgd5OIEW0eYUcP8yfhtoOIhLJkylYJ4=";
-  } // { inherit rev; };
-  isLibrary = false;
-  isExecutable = true;
-  libraryHaskellDepends = [
-    aeson base bytestring cabal-install-parsers Cabal-syntax containers
-    directory filepath frontmatter generic-lens-lite mtl parsec pretty
-    regex-applicative text
-  ];
-  executableHaskellDepends = [
-    base bytestring Cabal-syntax directory filepath
-    optparse-applicative
-  ];
-  doHaddock = false;
-  description = "Concatenate changelog entries into a single one";
-  license = lib.licenses.gpl3Plus;
-  mainProgram = "changelog-d";
-}
diff --git a/misc/changelog-d.nix b/misc/changelog-d.nix
deleted file mode 100644
index 1b20f4596..000000000
--- a/misc/changelog-d.nix
+++ /dev/null
@@ -1,31 +0,0 @@
-# Taken temporarily from <nixpkgs/pkgs/by-name/ch/changelog-d/package.nix>
-{
-  callPackage,
-  lib,
-  haskell,
-  haskellPackages,
-}:
-
-let
-  hsPkg = haskellPackages.callPackage ./changelog-d.cabal.nix { };
-
-  addCompletions = haskellPackages.generateOptparseApplicativeCompletions ["changelog-d"];
-
-  haskellModifications =
-    lib.flip lib.pipe [
-      addCompletions
-      haskell.lib.justStaticExecutables
-    ];
-
-  mkDerivationOverrides = finalAttrs: oldAttrs: {
-
-    version = oldAttrs.version + "-git-${lib.strings.substring 0 7 oldAttrs.src.rev}";
-
-    meta = oldAttrs.meta // {
-      homepage = "https://codeberg.org/roberth/changelog-d";
-      maintainers = [ lib.maintainers.roberth ];
-    };
-
-  };
-in
-  (haskellModifications hsPkg).overrideAttrs mkDerivationOverrides
diff --git a/package.nix b/package.nix
index 1392bbe62..3c4971605 100644
--- a/package.nix
+++ b/package.nix
@@ -8,7 +8,7 @@
   boehmgc,
   nlohmann_json,
   bison,
-  changelog-d,
+  build-release-notes,
   boost,
   brotli,
   bzip2,
@@ -159,7 +159,7 @@ in stdenv.mkDerivation (finalAttrs: {
     jq
     lsof
   ] ++ lib.optional stdenv.hostPlatform.isLinux util-linuxMinimal
-    ++ lib.optional (!officialRelease && buildUnreleasedNotes) changelog-d
+    ++ lib.optional (!officialRelease && buildUnreleasedNotes) build-release-notes
     ++ lib.optional internalApiDocs doxygen
     ++ lib.optionals buildWithMeson [
       meson