test: root-commit fixtures — (none) base, D2 loud-death pin, e2e chain

facts.test.sh: greenfield fixtures for all-zeros and empty event.before,
the bare root establishing labeled=no, and the D2 pin (an unresolvable
MERGE_SHA exits 128 and never reports base_ver=(none) — the test that
|| true would fail). release-chain.test.sh: chain() gains optional
repo/stub args; a -dev root commit is a green NOTICE ceremony=no, a bare
unlabeled root still refuses. Plus changelog.d/134.md.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

changelog.d/134.md

@@ -0,0 +1 @@
+- `lib/facts.sh` — a repository's first push to `main` (a root commit with no first parent) now reads `base_ver=(none)` and lets decide's table govern, instead of dying at exit 128 before establishing a fact; the no-base path skips the base fetch and `git show`, and an unresolvable head still fails loudly (#134).

test/facts.test.sh

@@ -146,6 +146,42 @@ adoptb_head="$(commit adoption-bare VERSION 0.1.0)"
 check "absent-at-base with a bare head still asks for the label" 0 "labeled=yes" \
   facts_in adoption-bare VERSION_SOURCE=file MERGE_SHA="$adoptb_head" EVENT_BEFORE="$adoptb_base" GH_STUB=labeled-yes
 
+# --- a root commit: no base tree at all (the repository's first push) --------
+
+# The first push to main IS a branch-create push (event.before all-zeros)
+# whose head has no first parent — there is no base, and the honest fact is
+# "(none)", not an exit-128 death at rev-parse. Both 0.2.0 drills hit the
+# death independently (#134). The -dev row consults no API (stub default),
+# which also asserts the no-base path runs no base fetch/show at all.
+repo greenfield
+green_head="$(commit greenfield VERSION 0.1.0-dev)"
+
+check "root commit, all-zeros event.before: base_ver=(none)" 0 "base_ver=(none)" \
+  facts_in greenfield VERSION_SOURCE=file MERGE_SHA="$green_head" EVENT_BEFORE="$ZEROS"
+check "root commit, empty event.before: base_ver=(none)" 0 "base_ver=(none)" \
+  facts_in greenfield VERSION_SOURCE=file MERGE_SHA="$green_head" EVENT_BEFORE=
+
+repo greenfield-bare
+greenb_head="$(commit greenfield-bare VERSION 0.1.0)"
+check "bare root commit still establishes labeled, so decide can refuse" 0 "labeled=no" \
+  facts_in greenfield-bare VERSION_SOURCE=file MERGE_SHA="$greenb_head" EVENT_BEFORE="$ZEROS" GH_STUB=labeled-no
+
+# The D2 pin: "no first parent" is detected, never inferred from a failed
+# command — an unresolvable MERGE_SHA is a loud death, not "(none)". A
+# `|| true` around the fallback would pass every case above and fail here.
+BAD_SHA="1111111111111111111111111111111111111111"
+check "an unresolvable MERGE_SHA still dies loudly" 128 "bad object" \
+  facts_in greenfield VERSION_SOURCE=file MERGE_SHA="$BAD_SHA" EVENT_BEFORE="$ZEROS"
+bad_out="$(facts_in greenfield VERSION_SOURCE=file MERGE_SHA="$BAD_SHA" EVENT_BEFORE="$ZEROS" 2>&1)"
+if printf '%s' "$bad_out" | grep -qF "base_ver=(none)"; then
+  echo "FAIL: an unresolvable MERGE_SHA must not be reported as base_ver=(none)"
+  printf '%s\n' "$bad_out" | sed 's/^/    /'
+  FAIL=$((FAIL + 1))
+else
+  echo "ok: an unresolvable MERGE_SHA is not reported as base_ver=(none)"
+  PASS=$((PASS + 1))
+fi
+
 # --- the package-json backend ------------------------------------------------
 
 repo pkg

test/release-chain.test.sh

@@ -69,12 +69,14 @@ git -C "$TMP/repo" add VERSION CHANGELOG.md
 git -C "$TMP/repo" commit -qm "release: 0.7.0"
 MERGE_SHA="$(git -C "$TMP/repo" rev-parse HEAD)"
 
-# chain <merge_sha> <event_before> — facts, then decide fed from facts'
+# chain <merge_sha> <event_before> [repo_dir] [stub_dir] — facts, then
-# output lines, then the notes extraction, printing each stage's result.
+# decide fed from facts' output lines, then the notes extraction, printing
+# each stage's result. The optional dirs default to the main fixture; the
+# greenfield cases below (#134) bring their own repo and stub.
 chain() {
   (
-    cd "$TMP/repo" || exit 1
+    cd "${3:-$TMP/repo}" || exit 1
-    facts_out="$(env PATH="$TMP/stub:$PATH" GITHUB_REPOSITORY=fixture/fixture \
+    facts_out="$(env PATH="${4:-$TMP/stub}:$PATH" GITHUB_REPOSITORY=fixture/fixture \
       GH_TOKEN=stub VERSION_SOURCE=file MERGE_SHA="$1" EVENT_BEFORE="$2" \
       bash "$FACTS")" || exit 1
     printf '%s\n' "$facts_out"
@@ -150,4 +152,51 @@ check "the post-release bump decides ceremony=no" 0 "ceremony=no" \
 check "an ordinary -dev merge decides ceremony=no" 0 "ceremony=no" \
   chain "$WORK2_SHA" "$BUMP_SHA"
 
+# --- the repository's first push to main: a root commit, no base (#134) ------
+
+# event.before is all-zeros and the head has no first parent. facts reads
+# base_ver=(none) instead of dying at rev-parse, and decide's table governs
+# from there: the guided bootstrap (-dev first commit, what CONSUMERS.md
+# tells a new repo to write) is a green NOTICE no-op — the doctrine's
+# promise held at the exact moment a consumer adopts the ceremony.
+ZEROS="0000000000000000000000000000000000000000"
+
+git init -q "$TMP/greenfield"
+git -C "$TMP/greenfield" config user.email fixture@example.invalid
+git -C "$TMP/greenfield" config user.name fixture
+printf '0.1.0-dev\n' >"$TMP/greenfield/VERSION"
+git -C "$TMP/greenfield" add VERSION
+git -C "$TMP/greenfield" commit -qm "root: adopt the ceremony at 0.1.0-dev"
+GREEN_SHA="$(git -C "$TMP/greenfield" rev-parse HEAD)"
+
+check "a greenfield -dev root commit decides ceremony=no, not a red run" 0 "ceremony=no" \
+  chain "$GREEN_SHA" "$ZEROS" "$TMP/greenfield"
+check "the greenfield no-op is a NOTICE" 0 "NOTICE:" \
+  chain "$GREEN_SHA" "$ZEROS" "$TMP/greenfield"
+
+# A bare first commit with no merged release-labeled PR must still refuse —
+# the reason the crash could not be `|| true`-ed away: a greenfield adoption
+# must never become a silent release. This stub answers the labeled query
+# with false.
+mkdir -p "$TMP/stub-unlabeled"
+cat >"$TMP/stub-unlabeled/gh" <<'EOF'
+#!/usr/bin/env bash
+if [ "$1" = api ]; then echo false; exit 0; fi
+echo "gh stub: unexpected call: gh $*" >&2
+exit 97
+EOF
+chmod +x "$TMP/stub-unlabeled/gh"
+
+git init -q "$TMP/greenfield-bare"
+git -C "$TMP/greenfield-bare" config user.email fixture@example.invalid
+git -C "$TMP/greenfield-bare" config user.name fixture
+printf '0.1.0\n' >"$TMP/greenfield-bare/VERSION"
+git -C "$TMP/greenfield-bare" add VERSION
+git -C "$TMP/greenfield-bare" commit -qm "root: bare 0.1.0, nobody declared a release"
+GREENB_SHA="$(git -C "$TMP/greenfield-bare" rev-parse HEAD)"
+
+check "a bare unlabeled root commit still refuses, creating nothing" 1 \
+  "no merged, release-labeled PR" \
+  chain "$GREENB_SHA" "$ZEROS" "$TMP/greenfield-bare" "$TMP/stub-unlabeled"
+
 summary