fnlfmt: Prevent unnecessary writes with --fix v1 PROPOSED

Oliver Vartiainen: 1
 Prevent unnecessary writes with --fix

 2 files changed, 9 insertions(+), 7 deletions(-)

[PATCH fnlfmt] Prevent unnecessary writes with --fix Export this patch

in order to allow tooling around fnlfmt to work right

Phil Hagelberg <phil@hagelb.org>

5 months ago

Thanks!

I realized this same logic would be useful for the --check
implementation, not just --fix, so I've added it to that as well.

I've applied and pushed.

-Phil

---
 cli.fnl    | 9 +++++----
 fnlfmt.fnl | 7 ++++---
 2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/cli.fnl b/cli.fnl
index 504fb6c..9e01c50 100644
--- a/cli.fnl
+++ b/cli.fnl
@@ -33,10 +33,11 @@
       (os.exit)))
 
 (fn fix [filename]
-  (let [new (format-file filename options)
-        f (assert (io.open filename :w))]
-    (f:write new)
-    (f:close)))
+  (let [(new changed?) (format-file filename options)]
+    (when changed? ; prevent unnecessary writes
+      (let [f (assert (io.open filename :w))]
+        (f:write new)
+        (f:close)))))
 
 (match arg
   [:--version] (print (.. "fnlfmt version " version))
diff --git a/fnlfmt.fnl b/fnlfmt.fnl
index 2700f86..d9b3042 100644
--- a/fnlfmt.fnl
+++ b/fnlfmt.fnl
@@ -396,8 +396,8 @@ When f returns a truthy value, recursively walks the children."
   (let [f (match filename
             "-" io.stdin
             _ (or (io.open filename :r) (abort filename)))
-        contents (f:read :*all)
-        parser (-> (fennel.stringStream contents)
+        original (f:read :*all)
+        parser (-> (fennel.stringStream original)
                    (fennel.parser filename {:comments (not no-comments)}))
         out []]
     (f:close)
@@ -420,6 +420,7 @@ When f returns a truthy value, recursively walks the children."
             (set skip-next? false)))
       (set prev-ast ast))
     (table.insert out "")
-    (table.concat out "\n")))
+    (let [formatted (table.concat out "\n")]
+      (values formatted (not= formatted original)))))
 
 {: fnlfmt : format-file :version :0.3.2-dev}
-- 
2.39.3 (Apple Git-145)

Phil Hagelberg <phil@hagelb.org>

5 months ago

Oliver Vartiainen <oliver@rakkine.fi> writes: