[elpa] externals/javaimp 4301371: Introduce javaimp-source-file-cache and use it

[Filipp Gunbin]

branch: externals/javaimp
commit 43013717e824b662cf14e76102439cd71c3fdd58
Author: Filipp Gunbin <fgunbin@fastmail.fm>
Commit: Filipp Gunbin <fgunbin@fastmail.fm>

    Introduce javaimp-source-file-cache and use it
---
 javaimp-util.el | 46 +++++++++++++++++++++++++++++++++--------
 javaimp.el      | 64 ++++++++++++++++++++++++++++++---------------------------
 2 files changed, 72 insertions(+), 38 deletions(-)

diff --git a/javaimp-util.el b/javaimp-util.el
index a4569b9..639474a 100644
--- a/javaimp-util.el
+++ b/javaimp-util.el
@@ -80,7 +80,7 @@ build tool output.  Can be let-bound to nil to suppress 
copying.")
 (cl-defstruct javaimp-id
   group artifact version)
 
-(cl-defstruct javaimp-cached-jar        ;jar or jmod
+(cl-defstruct javaimp-cached-file
   file read-ts classes)
 
 (cl-defstruct javaimp-scope
@@ -90,6 +90,11 @@ build tool output.  Can be let-bound to nil to suppress 
copying.")
   open-brace
   parent)
 
+(defsubst javaimp-print-id (id)
+  (format "%s:%s:%s"
+          (javaimp-id-artifact id)
+          (javaimp-id-group id)
+          (javaimp-id-version id)))
 
 
 ;; Xml
@@ -246,17 +251,42 @@ additionally tested by PRED."
 
 
 
-;; Other
-
-(defsubst javaimp-print-id (id)
-  (format "%s:%s:%s"
-          (javaimp-id-artifact id)
-          (javaimp-id-group id)
-          (javaimp-id-version id)))
+;; Files & caches
 
 (defsubst javaimp--get-file-ts (file)
   (nth 5 (file-attributes file)))
 
+(defun javaimp--get-file-classes-cached (file cache-sym class-reader)
+  "Return list of classes for FILE.  Use CACHE-SYM as a cache, it
+should be an alist with elements of the form (FILE
+. CACHED-FILE).  If not found in cache, or the cache is outdated,
+then classes are read using CLASS-READER, which should be a
+function of one argument, a FILE.  If that function throws an
+error, the cache for FILE is cleared."
+  (condition-case err
+      (let ((cached-file
+             (alist-get file (symbol-value cache-sym) nil nil #'string=)))
+        (when (or (not cached-file)
+                  ;; If the file doesn't exist this will be current
+                  ;; time, and thus condition always true
+                  (> (float-time (javaimp--get-file-ts file))
+                    (float-time (javaimp-cached-file-read-ts cached-file))))
+          (setq cached-file (make-javaimp-cached-file
+                            :file file
+                            :read-ts (javaimp--get-file-ts file)
+                            :classes (funcall class-reader file))))
+        (setf (alist-get file (symbol-value cache-sym) nil 'remove #'string=)
+              cached-file)
+        (javaimp-cached-file-classes cached-file))
+    (t
+     ;; Clear on any error
+     (setf (alist-get file (symbol-value cache-sym) nil 'remove #'string=) nil)
+     (signal (car err) (cdr err)))))
+
+
+
+;; System
+
 ;; TODO use functions `cygwin-convert-file-name-from-windows' and
 ;; `cygwin-convert-file-name-to-windows' when they are available
 ;; instead of calling `cygpath'.  See
diff --git a/javaimp.el b/javaimp.el
index e2a1e37..cbd1283 100644
--- a/javaimp.el
+++ b/javaimp.el
@@ -75,6 +75,7 @@
 (require 'javaimp-maven)
 (require 'javaimp-gradle)
 (require 'javaimp-parse)
+(require 'javaimp-util)
 (require 'cc-mode)                      ;for java-mode-syntax-table
 (require 'imenu)
 
@@ -184,9 +185,15 @@ A handler function takes one argument, a FILE.")
 (defvar javaimp-project-forest nil
   "Visited projects")
 
-(defvar javaimp-jar-cache nil
-  "Jar cache, an alist of (FILE . JAR), where FILE is expanded
-file name and JAR is javaimp-cached-jar struct.")
+(defvar javaimp-jar-file-cache nil
+  "Jar file cache, an alist of (FILE . CACHED-FILE), where FILE is
+expanded file name and CACHED-FILE is javaimp-cached-file
+struct.")
+
+(defvar javaimp-source-file-cache nil
+  "Source file cache, an alist of (FILE . CACHED-FILE), where FILE
+is expanded file name and CACHED-FILE is javaimp-cached-file
+struct.")
 
 (defvar javaimp-syntax-table
   (make-syntax-table java-mode-syntax-table) ;TODO don't depend
@@ -267,14 +274,14 @@ any module's source file."
       (message "Loaded project from %s" file))))
 
 
-;; Dependency jars
+;; Dependencies
 
 (defun javaimp--update-module-maybe (node)
   (let ((module (javaimp-node-contents node))
        need-update ids)
     ;; check if deps are initialized
     (unless (javaimp-module-dep-jars module)
-      (message "Loading dependencies for module: %s" (javaimp-module-id 
module))
+      (message "Will load dependencies for %s" (javaimp-module-id module))
       (setq need-update t))
     ;; check if this or any parent build file has changed since we
     ;; loaded the module
@@ -303,22 +310,10 @@ any module's source file."
             (current-time)))))
 
 (defun javaimp--get-jar-classes (file)
-  (condition-case err
-      (let ((jar (alist-get file javaimp-jar-cache nil nil #'equal)))
-        (when (or (not jar)
-                  ;; If the file doesn't exist this will be current
-                  ;; time, and thus condition always true
-                  (> (float-time (javaimp--get-file-ts file))
-                    (float-time (javaimp-cached-jar-read-ts jar))))
-          (setq jar (make-javaimp-cached-jar
-                    :file file
-                    :read-ts (javaimp--get-file-ts file)
-                    :classes (javaimp--read-jar-classes file))))
-        (setf (alist-get file javaimp-jar-cache) jar)
-        (javaimp-cached-jar-classes jar))
-    (t
-     (setf (alist-get file javaimp-jar-cache nil 'remove #'equal) nil)
-     (signal (car err) (cdr err)))))
+  (javaimp--get-file-classes-cached
+   file
+   'javaimp-jar-file-cache
+   #'javaimp--read-jar-classes))
 
 (defun javaimp--read-jar-classes (file)
   "Read FILE which should be a .jar or a .jmod and return classes
@@ -502,20 +497,28 @@ If there's no such directive, then the last resort is just
 
 (defun javaimp--get-file-classes (file)
   (if-let ((buf (get-file-buffer file)))
+      ;; Don't use cache, just collect what we have in buffer
       (with-current-buffer buf
         (save-excursion
           (save-restriction
             (widen)
             (javaimp--get-buffer-classes))))
-    (with-temp-buffer
-      (insert-file-contents file)
-      ;; We need only class-likes, and this is temp buffer, so for
-      ;; efficiency avoid parsing anything else
-      (let ((javaimp--parse-scope-hook #'javaimp--parse-scope-class))
-        (javaimp--get-buffer-classes)))))
+    (javaimp--get-file-classes-cached
+     file
+     'javaimp-source-file-cache
+     #'javaimp--read-source-classes)))
+
+(defun javaimp--read-source-classes (file)
+  (with-temp-buffer
+    (insert-file-contents file)
+    ;; We need only class-likes, and this is temp buffer, so for
+    ;; efficiency avoid parsing anything else
+    (let ((javaimp--parse-scope-hook #'javaimp--parse-scope-class))
+      (javaimp--get-buffer-classes))))
 
 (defun javaimp--get-buffer-classes ()
-  "Return fully-qualified names of all class-like scopes."
+  "Return fully-qualified names of all class-like scopes in the
+current buffer."
   (let ((package (javaimp--parse-get-package))
         (scopes (javaimp--parse-get-all-scopes
                  (lambda (scope)
@@ -815,8 +818,9 @@ start (`javaimp-scope-start') instead."
 
 (defun javaimp-flush-cache ()
   "Flush all caches."
-  (setq javaimp-jar-cache nil))
-
+  (interactive)
+  (setq javaimp-jar-file-cache nil
+        javaimp-source-file-cache nil))
 
 (provide 'javaimp)