Format ocp-indent with itself

.github/workflows/main.yml

@@ -40,6 +40,7 @@ jobs:
       - run: opam exec -- dune build @install
       - run: opam install . --deps-only -t
       - run: opam exec -- dune runtest
+      - run: opam exec -- dune build @fmt
       - run: opam config report
       - run: opam install .
       - run: opam exec ocp-indent --help

.gitignore

@@ -5,7 +5,6 @@ ocp-build.root*
 _obuild
 config.log
 config.status
-ocp-indent
 src/indentVersion.ml
 *~
 version.ocp
@@ -18,4 +17,4 @@ src/buildable_targets.list
 **/.fe.sexp
 _build
 .merlin
-*.install
+*.install

CHANGELOG.md

@@ -6,6 +6,8 @@
 + Fix "Missing ‘lexical-binding’ cookie" warning in Emacs (#329, @nojb)
 + Fix a bug where ocp-indent translate LF to CRLF when run on Windows instead
   of preserving the input's newlines. (#334, @nojb)
++ Add `ocp-indent-gen-rules` to support `dune fmt` like workflow with ocp-indent
+  (#333, @NathanReb)
 
 ## 1.8.1
 * tiny API change to help with the detection of top-level phrase boundaries

README.md

@@ -112,6 +112,44 @@ line like:
 will enable you to have the indentation after `in` setup to 2 locally on this
 file.
 
+## Autoformat files with ocp-indent in dune
+
+`dune fmt` or `dune build @fmt` can be used to format dune and OCaml files
+with `ocamlformat`. This can prove a convenient workflow for new projects so we
+made it available to `ocp-indent` users as well.
+
+First you need to disable the default formatting rules for OCaml source files
+by adding the following to your `dune-project`:
+```dune
+(formatting (enabled_for dune))
+```
+
+`dune fmt` won't try to format your OCaml files with `ocamlformat` from there.
+
+The `ocp-indent` formatting rules need to be enabled on a per-directory basis by
+adding the following dune rules to the `dune` file:
+
+```dune
+;; Auto indent files with `dune build @fmt`
+
+(subdir
+ run
+ (dynamic_include ../rules/dune.ocp-indent))
+
+(subdir
+ rules
+ (rule
+  (deps
+   (glob_files ../*.{ml,mli}))
+  (target dune.ocp-indent)
+  (action
+   (run ocp-indent-gen-rules -o %{target}))))
+```
+
+`ocp-indent-gen-rules` will generate promotion based formatting rules for each
+`.ml` and `.mli` files in this folder. You can simply use the same
+`dune build @fmt`/`dune promote` workflow as with ocamlformat.
+
 
 ## How does it compare to tuareg ?
 

doc/dune

@@ -1,10 +1,10 @@
 (rule
  (targets ocp-indent.1)
  (action
-  (with-stdout-to %{targets}
-   (run %{bin:ocp-indent} --help=groff)))
-)
+  (with-stdout-to
+   %{targets}
+   (run %{bin:ocp-indent} --help=groff))))
+
 (install
  (section man)
- (files ocp-indent.1)
-)
+ (files ocp-indent.1))

dune-project

@@ -2,3 +2,5 @@
 
 (name ocp-indent)
 (version 1.8.1)
+
+(formatting (enabled_for dune))

src/ocp-indent-dynlink/dune

@@ -2,5 +2,19 @@
  (name ocp_indent_dynlink)
  (public_name ocp-indent.dynlink)
  (wrapped false)
- (libraries findlib dynlink ocp-indent.lexer ocp-indent.utils)
-)
+ (libraries findlib dynlink ocp-indent.lexer ocp-indent.utils))
+
+;; Auto indent files with `dune build @fmt`
+
+(subdir
+ run
+ (dynamic_include ../rules/dune.ocp-indent))
+
+(subdir
+ rules
+ (rule
+  (deps
+   (glob_files ../*.{ml,mli}))
+  (target dune.ocp-indent)
+  (action
+   (run ocp-indent-gen-rules -o %{target}))))

src/ocp-indent-gen-rules/dune

@@ -0,0 +1,24 @@
+(rule
+ (with-stdout-to
+  version.ml
+  (echo "let v = \"%{version:ocp-indent}\"")))
+
+(executable
+ (name main)
+ (public_name ocp-indent-gen-rules)
+ (libraries cmdliner))
+
+;; Auto indent files with `dune build @fmt`
+
+(subdir
+ run
+ (dynamic_include ../rules/dune.ocp-indent))
+
+(subdir
+ rules
+ (rule
+  (deps
+   (glob_files ../*.{ml,mli}))
+  (target dune.ocp-indent)
+  (action
+   (run ocp-indent-gen-rules -o %{target}))))

src/ocp-indent-gen-rules/main.ml

@@ -0,0 +1,82 @@
+let exe_name = "ocp-indent-gen-rules"
+
+let named f = Cmdliner.Term.(app (const f))
+
+let ignore =
+  let open Cmdliner.Arg in
+  let doc = "Comma separated list of files that should not be indented" in
+  named
+    (fun x -> `Ignore x)
+    (value & opt (list string) [] & info ~doc ["ignore"])
+
+let alias =
+  let open Cmdliner.Arg in
+  let doc = "The alias for the ocp-indent rules, default is fmt" in
+  named
+    (fun x -> `Alias x)
+    (value & opt string "fmt" & info ~doc ["alias"])
+
+let static =
+  let open Cmdliner.Arg in
+  let doc =
+    "Generate rules for a regular include stanza rather than a dynamic_include"
+  in
+  named
+    (fun x -> `Static x)
+    (value & flag & info ~doc ["static"])
+
+let output =
+  let open Cmdliner.Arg in
+  let docv = "OUTFILE" in
+  let doc = "Writes rules to $(docv). When absent, writes rules to stdout." in
+  named
+    (fun x -> `Output x)
+    (value & opt (some string) None & info ~doc ~docv ["o"])
+
+let print_rules ~ignore ~alias ~static oc file =
+  let source_file = if static then file else "../" ^ file in
+  if List.mem file ignore then
+    ()
+  else
+    match Filename.extension file with
+    | ".ml" | ".mli" ->
+        let formatted_ext = "fmtd" in
+        let pf fmt = Printf.fprintf oc (fmt ^^ "\n") in
+        pf "(rule";
+        pf " (target %s.%s)" file formatted_ext;
+        pf " (action (run ocp-indent %%{dep:%s} -o %%{target})))" source_file;
+        pf "";
+        pf "(rule";
+        pf " (alias %s)" alias;
+        pf " (action (diff %s %s.%s)))" source_file file formatted_ext;
+        pf ""
+    | _ -> ()
+
+let with_output ~f output =
+  match output with
+  | None -> f stdout
+  | Some file ->
+      let oc = open_out file in
+      f oc;
+      close_out oc
+
+let run (`Ignore ignore) (`Alias alias) (`Static static)
+    (`Output output) =
+  let src_dir = if static then Sys.getcwd () else ".." in
+  let files = Sys.readdir src_dir in
+  with_output output
+    ~f:(fun oc ->
+        Array.sort String.compare files;
+        Array.iter (print_rules ~ignore ~alias ~static oc) files)
+
+let term =
+  let open Cmdliner.Term in
+  const run $ ignore $ alias $ static $ output
+
+let info =
+  let open Cmdliner in
+  Cmd.info exe_name ~version:Version.v ~exits:Cmd.Exit.defaults
+    ~doc:"Generate ocp-indent dune rules"
+
+let () =
+  exit (Cmdliner.Cmd.eval (Cmdliner.Cmd.v info term))

src/ocp-indent-lexer/approx_tokens.ml

@@ -40,13 +40,13 @@ type token =
   | COLONEQUAL
   | COLONGREATER
   | COMMA
-    (* Start of comment from code *)
+  (* Start of comment from code *)
   | COMMENT
-    (* Start of inline code section within comment: "{[" *)
+  (* Start of inline code section within comment: "{[" *)
   | OCAMLDOC_CODE
-    (* Start of verbatim section within comment: "{v" *)
+  (* Start of verbatim section within comment: "{v" *)
   | OCAMLDOC_VERB
-    (* Continuation of comment after a closed ocamldoc code or verb section *)
+  (* Continuation of comment after a closed ocamldoc code or verb section *)
   | COMMENTCONT
   | CONSTRAINT
   | DO
@@ -170,13 +170,13 @@ let to_string = function
   | COLONEQUAL -> "COLONEQUAL"
   | COLONGREATER -> "COLONGREATER"
   | COMMA -> "COMMA"
-    (* Start of comment from code *)
+  (* Start of comment from code *)
   | COMMENT -> "COMMENT"
-    (* Start of inline code section within comment: "{[" *)
+  (* Start of inline code section within comment: "{[" *)
   | OCAMLDOC_CODE -> "OCAMLDOC_CODE"
-    (* Start of verbatim section within comment: "{v" *)
+  (* Start of verbatim section within comment: "{v" *)
   | OCAMLDOC_VERB -> "OCAMLDOC_VERB"
-    (* Continuation of comment after a closed ocamldoc code or verb section *)
+  (* Continuation of comment after a closed ocamldoc code or verb section *)
   | COMMENTCONT -> "COMMENTCONT"
   | CONSTRAINT -> "CONSTRAINT"
   | DO -> "DO"

src/ocp-indent-lexer/dune

@@ -3,5 +3,19 @@
 (library
  (name ocp_indent_lexer)
  (public_name ocp-indent.lexer)
- (wrapped false)
-)
+ (wrapped false))
+
+;; Auto indent files with `dune build @fmt`
+
+(subdir
+ run
+ (dynamic_include ../rules/dune.ocp-indent))
+
+(subdir
+ rules
+ (rule
+  (deps
+   (glob_files ../*.{ml,mli}))
+  (target dune.ocp-indent)
+  (action
+   (run ocp-indent-gen-rules --ignore approx_lexer.ml -o %{target}))))

src/ocp-indent-lib/dune

@@ -3,5 +3,19 @@
  (wrapped false)
  (public_name ocp-indent.lib)
  (libraries ocp-indent.utils)
- (flags :standard -w -9 -warn-error -57)
-)
+ (flags :standard -w -9 -warn-error -57))
+
+;; Auto indent files with `dune build @fmt`
+
+(subdir
+ run
+ (dynamic_include ../rules/dune.ocp-indent))
+
+(subdir
+ rules
+ (rule
+  (deps
+   (glob_files ../*.{ml,mli}))
+  (target dune.ocp-indent)
+  (action
+   (run ocp-indent-gen-rules -o %{target}))))