test: add terminal coverage summary helper

2 files changed, 123 insertions, 0 deletions

diff --git a/scripts/coverage-summary.el b/scripts/coverage-summary.el
new file mode 100644
index 00000000..4947171f
--- /dev/null
+++ b/scripts/coverage-summary.el
@@ -0,0 +1,57 @@
+;;; coverage-summary.el --- Terminal summary for SimpleCov module coverage -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; Batch helper for `make coverage' and `make coverage-summary'.
+;; Reuses coverage-core's SimpleCov parser and whole-project formatter so the
+;; terminal table matches the editor's whole-project coverage semantics.
+
+;;; Code:
+
+(require 'coverage-core)
+
+(defun cj/coverage-summary--copy-lines (lines)
+  "Return a copy of hash table LINES."
+  (let ((copy (make-hash-table :test 'eql)))
+	(when (hash-table-p lines)
+	  (maphash (lambda (line value)
+				 (puthash line value copy))
+			   lines))
+	copy))
+
+(defun cj/coverage-summary--modules-only (table module-dir project-root)
+  "Filter coverage TABLE to files under MODULE-DIR.
+
+Returned keys are relative to PROJECT-ROOT for readable terminal output."
+  (let ((result (make-hash-table :test 'equal))
+		(module-dir (file-name-as-directory (expand-file-name module-dir)))
+		(project-root (file-name-as-directory (expand-file-name project-root))))
+	(maphash
+	 (lambda (path lines)
+	   (let ((absolute-path (expand-file-name path)))
+		 (when (string-prefix-p module-dir absolute-path)
+		   (puthash (file-relative-name absolute-path project-root)
+					(cj/coverage-summary--copy-lines lines)
+					result))))
+	 table)
+	result))
+
+(defun cj/coverage-summary-text (report-file module-dir project-root)
+  "Return a whole-project coverage summary for MODULE-DIR from REPORT-FILE."
+  (let* ((covered (cj/coverage-summary--modules-only
+				   (cj/--coverage-parse-simplecov report-file)
+				   module-dir
+				   project-root))
+		 (executable (cj/coverage-summary--modules-only
+					  (cj/--coverage-simplecov-executable-lines report-file)
+					  module-dir
+					  project-root))
+		 (records (cj/--coverage-intersect covered executable)))
+	(cj/--coverage-format-summary records "modules/")))
+
+(defun cj/coverage-print-module-summary (report-file module-dir project-root)
+  "Print a whole-project coverage summary for MODULE-DIR from REPORT-FILE."
+  (princ "\n")
+  (princ (cj/coverage-summary-text report-file module-dir project-root)))
+
+(provide 'coverage-summary)
+;;; coverage-summary.el ends here
diff --git a/tests/test-coverage-summary.el b/tests/test-coverage-summary.el
new file mode 100644
index 00000000..01c9efa0
--- /dev/null
+++ b/tests/test-coverage-summary.el
@@ -0,0 +1,66 @@
+;;; test-coverage-summary.el --- Tests for terminal coverage summary -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; Unit tests for the batch helper used by `make coverage-summary'.
+
+;;; Code:
+
+(require 'ert)
+
+(add-to-list 'load-path (expand-file-name "modules" user-emacs-directory))
+(add-to-list 'load-path (expand-file-name "scripts" user-emacs-directory))
+(require 'coverage-summary)
+
+(defun test-coverage-summary--write-json (content)
+  "Write CONTENT to a temp file; return its path."
+  (let ((file (make-temp-file "test-coverage-summary-" nil ".json")))
+	(with-temp-file file
+	  (insert content))
+	file))
+
+(ert-deftest test-coverage-summary-modules-only ()
+  "Normal: summary includes modules files and ignores non-module files."
+  (let* ((root (file-name-as-directory (make-temp-file "coverage-root-" t)))
+		 (module-a (expand-file-name "modules/a.el" root))
+		 (module-b (expand-file-name "modules/b.el" root))
+		 (other (expand-file-name "tests/test-a.el" root))
+		 (content (format
+				   "{\"run\":{\"coverage\":{\"%s\":[1,0,null,1],\"%s\":[0,0],\"%s\":[1,1]}}}"
+				   module-a module-b other))
+		 (file (test-coverage-summary--write-json content)))
+	(unwind-protect
+		(let ((output (cj/coverage-summary-text
+					   file
+					   (expand-file-name "modules" root)
+					   root)))
+		  (should (string-match-p "modules/a\\.el" output))
+		  (should (string-match-p "modules/b\\.el" output))
+		  (should-not (string-match-p "tests/test-a\\.el" output))
+		  (should (string-match-p "2 of 5" output)))
+	  (delete-file file)
+	  (delete-directory root t))))
+
+(ert-deftest test-coverage-summary-sorts-worst-first ()
+  "Normal: module rows use the same worst-first sorting as the editor summary."
+  (let* ((root (file-name-as-directory (make-temp-file "coverage-root-" t)))
+		 (low (expand-file-name "modules/low.el" root))
+		 (high (expand-file-name "modules/high.el" root))
+		 (content (format
+				   "{\"run\":{\"coverage\":{\"%s\":[0,0,1,1],\"%s\":[1,1]}}}"
+				   low high))
+		 (file (test-coverage-summary--write-json content)))
+	(unwind-protect
+		(let* ((output (cj/coverage-summary-text
+						file
+						(expand-file-name "modules" root)
+						root))
+			   (pos-low (string-match "modules/low\\.el" output))
+			   (pos-high (string-match "modules/high\\.el" output)))
+		  (should pos-low)
+		  (should pos-high)
+		  (should (< pos-low pos-high)))
+	  (delete-file file)
+	  (delete-directory root t))))
+
+(provide 'test-coverage-summary)
+;;; test-coverage-summary.el ends here