Re-organize CI.

.github/workflows/ci.yml

@@ -10,11 +10,15 @@ jobs:
     strategy:
       matrix:
         emacs_version: [25, 26, 27, 28]
+        make_target: ['checkdoc', 'longlines', 'test', 'compile']
     steps:
       - name: Checkout
         uses: actions/checkout@v2
       - name: CI
         env:
           VERSION: ${{ matrix.emacs_version }}
-        run: >-
-          make docker CMD="make -k compile checkdoc longlines test"
+          TARGET: ${{ matrix.make_target }}
+        run: |
+          echo "Emacs version is: $VERSION"
+          >-
+            make docker CMD="make -k $TARGET VERSION=$VERSION"

Makefile

@@ -5,6 +5,17 @@ EMACS ?= emacs
 
 # The order is important for compilation.
 for_compile := prescient.el $(wildcard *-prescient.el)
+# Don't bother testing compilation of the Vertico and Corfu packages
+# for Emacs versions that Vertico/Corfu doesn't support.
+ifneq ($(VERSION),undefined)
+  $(info VERSION is $(VERSION))
+  ifeq (1, $(strip $(shell expr $(VERSION) \< 27)))
+    $(info Inside condition)
+    for_compile := $(subst vertico-prescient.el,,$(for_compile))
+    for_compile := $(subst corfu-prescient.el,,$(for_compile))
+  endif
+endif
+$(info for_compile is $(for_compile))
 for_checkdoc := prescient.el $(wildcard *-prescient.el)
 for_longlines := $(wildcard *.el *.md *.yml) Makefile