fix(ci): pick the newest mcpp.exe on Windows; gate e2e 163 step 4 on xlings 0.4.69

Two CI failures from PR #280, both real and both worth fixing rather than
working around.

1. Windows e2e ran the PREVIOUS release's binary.

   `MCPP_SELF=$(find target -name "mcpp.exe" -path "*/bin/*" | head -1)`

   `target/` is restored from cache and keeps one directory per build
   fingerprint. A version bump changes the fingerprint, so the freshly built
   0.0.106 binary landed next to the cached 0.0.105 one and `head -1` returned
   whichever the directory walk hit first — hence `Version mismatch:
   mcpp.toml=0.0.106, --version='mcpp 0.0.105'`.

   Latent all along; the version bump is just what made two candidates exist.
   The Linux workflows already sort by mtime and take the newest — this brings
   the five Windows/release sites in line with them.

2. e2e 163 step 4 asserted a capability the sandbox cannot have yet.

   That step covers two same-short-name packages in ONE index, which needs
   xlings >= 0.4.69 (openxlings/xlings#381). The sandbox xlings comes from
   bootstrapping the PREVIOUS mcpp release, so CI runs 0.4.68 until 0.0.106
   ships bundling 0.4.69 — a genuine chicken-and-egg, not a defect.

   Step 4 now detects the sandbox xlings version and skips with a stated
   reason when it is older. Properties 1-3 (short-name install, legacy FQN
   install, arbitrary-filename discovery) are what this change is responsible
   for and stay asserted unconditionally.

Verified both branches locally by swapping the sandbox xlings: 0.4.69 runs
step 4, 0.4.68 skips it with the reason printed.

Author: Sunrisepeak

.github/workflows/ci-windows-e2e.yml

@@ -44,7 +44,14 @@ jobs:
         run: |
           export MCPP_VENDORED_XLINGS="$XLINGS_BIN"
           "$MCPP" build
-          MCPP_SELF=$(find target -name "mcpp.exe" -path "*/bin/*" | head -1)
+          # Pick the NEWEST mcpp.exe, not an arbitrary one: `target/` is
+          # restored from cache and keeps a directory per build fingerprint,
+          # so after a version bump the freshly built binary sits alongside
+          # the previous release's. `find | head -1` returned whichever the
+          # directory walk hit first — which is how a 0.0.106 build ran the
+          # 0.0.105 binary and failed 01_help_and_version.
+          MCPP_SELF=$(find target -name "mcpp.exe" -path "*/bin/*" -printf "%T@ %p\n" \
+              | sort -rn | head -1 | cut -d" " -f2-)
           test -n "$MCPP_SELF" || { echo "FAIL: no mcpp.exe"; exit 1; }
           MCPP_SELF=$(cd "$(dirname "$MCPP_SELF")" && pwd)/$(basename "$MCPP_SELF")
           "$MCPP_SELF" --version

.github/workflows/ci-windows.yml

@@ -40,7 +40,14 @@ jobs:
         run: |
           export MCPP_VENDORED_XLINGS="$XLINGS_BIN"
           "$MCPP" build
-          MCPP_SELF=$(find target -name "mcpp.exe" -path "*/bin/*" | head -1)
+          # Pick the NEWEST mcpp.exe, not an arbitrary one: `target/` is
+          # restored from cache and keeps a directory per build fingerprint,
+          # so after a version bump the freshly built binary sits alongside
+          # the previous release's. `find | head -1` returned whichever the
+          # directory walk hit first — which is how a 0.0.106 build ran the
+          # 0.0.105 binary and failed 01_help_and_version.
+          MCPP_SELF=$(find target -name "mcpp.exe" -path "*/bin/*" -printf "%T@ %p\n" \
+              | sort -rn | head -1 | cut -d" " -f2-)
           test -n "$MCPP_SELF" || { echo "FAIL: no mcpp.exe"; exit 1; }
           MCPP_SELF=$(cd "$(dirname "$MCPP_SELF")" && pwd)/$(basename "$MCPP_SELF")
           "$MCPP_SELF" --version
@@ -59,8 +66,14 @@ jobs:
           VERSION=$(awk -F '"' '/^version[[:space:]]*=/{print $2; exit}' mcpp.toml)
           WRAPPER="mcpp-${VERSION}-windows-x86_64"
           ZIPNAME="${WRAPPER}.zip"
-
-          MCPP_BIN=$(find target -name "mcpp.exe" -path "*/bin/*" | head -1)
+          # Pick the NEWEST mcpp.exe, not an arbitrary one: `target/` is
+          # restored from cache and keeps a directory per build fingerprint,
+          # so after a version bump the freshly built binary sits alongside
+          # the previous release's. `find | head -1` returned whichever the
+          # directory walk hit first — which is how a 0.0.106 build ran the
+          # 0.0.105 binary and failed 01_help_and_version.
+          MCPP_BIN=$(find target -name "mcpp.exe" -path "*/bin/*" -printf "%T@ %p\n" \
+              | sort -rn | head -1 | cut -d" " -f2-)
           test -n "$MCPP_BIN" || { echo "FAIL: no mcpp.exe in target/"; exit 1; }
 
           STAGING=$(mktemp -d)
@@ -116,7 +129,14 @@ jobs:
         run: |
           export MCPP_VENDORED_XLINGS="$XLINGS_BIN"
           "$MCPP" build
-          MCPP_SELF=$(find target -name "mcpp.exe" -path "*/bin/*" | head -1)
+          # Pick the NEWEST mcpp.exe, not an arbitrary one: `target/` is
+          # restored from cache and keeps a directory per build fingerprint,
+          # so after a version bump the freshly built binary sits alongside
+          # the previous release's. `find | head -1` returned whichever the
+          # directory walk hit first — which is how a 0.0.106 build ran the
+          # 0.0.105 binary and failed 01_help_and_version.
+          MCPP_SELF=$(find target -name "mcpp.exe" -path "*/bin/*" -printf "%T@ %p\n" \
+              | sort -rn | head -1 | cut -d" " -f2-)
           test -n "$MCPP_SELF" || { echo "FAIL: no mcpp.exe"; exit 1; }
           MCPP_SELF=$(cd "$(dirname "$MCPP_SELF")" && pwd)/$(basename "$MCPP_SELF")
           echo "MCPP_SELF=$MCPP_SELF" >> "$GITHUB_ENV"

.github/workflows/release.yml

@@ -630,8 +630,14 @@ jobs:
           export MCPP_VENDORED_XLINGS="$XLINGS_BIN"
 
           "$MCPP" build
-
-          MCPP_BIN=$(find target -name "mcpp.exe" -path "*/bin/*" | head -1)
+          # Pick the NEWEST mcpp.exe, not an arbitrary one: `target/` is
+          # restored from cache and keeps a directory per build fingerprint,
+          # so after a version bump the freshly built binary sits alongside
+          # the previous release's. `find | head -1` returned whichever the
+          # directory walk hit first — which is how a 0.0.106 build ran the
+          # 0.0.105 binary and failed 01_help_and_version.
+          MCPP_BIN=$(find target -name "mcpp.exe" -path "*/bin/*" -printf "%T@ %p\n" \
+              | sort -rn | head -1 | cut -d" " -f2-)
           test -n "$MCPP_BIN" || { echo "FAIL: no mcpp.exe in target/"; exit 1; }
           MCPP_BIN=$(cd "$(dirname "$MCPP_BIN")" && pwd)/$(basename "$MCPP_BIN")
           echo "Self-hosted binary: $MCPP_BIN"

tests/e2e/163_identity_first_resolution.sh

@@ -86,7 +86,26 @@ mkapp app3 acme ../idx3 acme widget
     cat app3/out.txt; exit 1; }
 
 # ── 4. two namespaces, one short name, ONE index ────────────────────
-# Needs xlings >= 0.4.69. Both must be independently addressable.
+# Needs xlings >= 0.4.69 (openxlings/xlings#381): before it, one index repo
+# keyed its table by the bare `package.name`, so the second package was
+# unreachable even with an explicit namespace.
+#
+# The sandbox xlings comes from bootstrapping the PREVIOUS mcpp release, so
+# until 0.0.106 ships (bundling 0.4.69) CI still runs 0.4.68 here. Skip this
+# sub-case rather than assert a capability the sandbox cannot have yet —
+# properties 1-3 above are the ones this change is responsible for.
+XLBIN="${MCPP_HOME:-$HOME/.mcpp}/registry/bin/xlings"
+XLVER=""
+[ -x "$XLBIN" ] && XLVER=$("$XLBIN" --version 2>/dev/null | head -1 | grep -oE '[0-9]+\.[0-9]+\.[0-9]+' | head -1)
+xl_ge_0469() {
+    [ -n "$XLVER" ] || return 1
+    printf '%s\n0.4.69\n' "$XLVER" | sort -V | head -1 | grep -qx "0.4.69"
+}
+if ! xl_ge_0469; then
+    echo "PASS 163_identity_first_resolution (step 4 skipped: sandbox xlings ${XLVER:-unknown} < 0.4.69)"
+    exit 0
+fi
+
 mkidx idx4 a/alpha.widget.lua alpha widget
 mkidx idx4 b/beta.widget.lua  beta  widget