Compile files individually in CI

We just sprinkle some eval-when-compiles around for older Emacs.  We can remove
them when the CI no longer supports Emacs 25.1.

.github/workflows/test.yml

@@ -58,7 +58,7 @@ jobs:
     - name: Byte compilation
       run: emacs --eval "(setq byte-compile-error-on-warn (>= emacs-major-version 26))" -L . --batch -f batch-byte-compile ./*.el
     - name: Tests
-      run: nix shell ${{ matrix.ledger_version || 'nixpkgs#ledger' }} --print-build-logs -c ./makem.sh test -vv --compile-batch
+      run: nix shell ${{ matrix.ledger_version || 'nixpkgs#ledger' }} --print-build-logs -c ./makem.sh test -vv
     # This is currently for information only, since a lot of docstrings need fixing up
     - name: Checkdoc
       run: make lint-checkdoc || true

ledger-mode.el

@@ -30,6 +30,8 @@
 
 ;;; Code:
 
+(eval-when-compile
+  (require 'subr-x))                    ;for `when-let' in Emacs <26
 (require 'ledger-regex)
 (require 'org)
 (require 'ledger-commodities)

ledger-occur.el

@@ -30,6 +30,8 @@
 ;;; Code:
 
 (require 'cl-lib)
+(eval-when-compile
+  (require 'subr-x))                    ;for `when-let' in Emacs <26
 (require 'ledger-navigate)
 
 (defconst ledger-occur-overlay-property-name 'ledger-occur-custom-buffer-grep)

ledger-post.el

@@ -23,6 +23,8 @@
 ;;; Commentary:
 ;; Utility functions for dealing with postings.
 
+(eval-when-compile
+  (require 'subr-x)) ;for `when-let', `string-empty-p', `string-trim' in Emacs <26
 (require 'ledger-regex)
 (require 'ledger-navigate)
 

ledger-reconcile.el

@@ -27,6 +27,8 @@
 
 ;;; Code:
 
+(eval-when-compile
+  (require 'subr-x))                    ;`if-let', `when-let' in Emacs <26
 (require 'easymenu)
 (require 'ledger-init)
 

ledger-xact.el

@@ -25,6 +25,8 @@
 
 ;;; Code:
 
+(eval-when-compile
+  (require 'subr-x))                    ;`if-let', `when-let' in Emacs <26
 (require 'eshell)
 (require 'ledger-regex)
 (require 'ledger-navigate)