[java] classpath and frontend fixes

Summary:
- Remove dead argument in function in JMain.
- Document order of constructed classpath.
- Stop asking repeatedly for the cwd in `add_source_file`.
- Improve exception safety and readability in `load_from_verbose_output`.

Reviewed By: ezgicicek

Differential Revision: D20290519

fbshipit-source-id: 86c32dcdf

infer/src/java/jClasspath.ml

@@ -52,16 +52,20 @@ let read_package_declaration source_file =
   Utils.with_file_in path ~f:loop |> Option.value ~default:""
 
 
-let add_source_file path map =
+let add_source_file =
+  let cwd = lazy (Sys.getcwd ()) in
   let convert_to_absolute p =
-    if Filename.is_relative p then Filename.concat (Sys.getcwd ()) p else p
+    if Filename.is_relative p then Filename.concat (Lazy.force cwd) p else p
   in
+  fun path map ->
     let basename = Filename.basename path in
     let entry =
       let current_source_file = SourceFile.from_abs_path (convert_to_absolute path) in
-    try
+      match String.Map.find map basename with
-      match String.Map.find_exn map basename with
+      | None ->
-      | Singleton previous_source_file ->
+          (* Most common case: there is no conflict with the base name of the source file *)
+          Singleton current_source_file
+      | Some (Singleton previous_source_file) ->
           (* Another source file with the same base name has been found.
              Reading the package from the source file to resolve the ambiguity
              only happens in this case *)
@@ -71,24 +75,19 @@ let add_source_file path map =
             [(current_package, current_source_file); (previous_package, previous_source_file)]
           in
           Duplicate source_list
-      | Duplicate previous_source_files ->
+      | Some (Duplicate previous_source_files) ->
           (* Two or more source file with the same base name have been found *)
           let current_package = read_package_declaration current_source_file in
           Duplicate ((current_package, current_source_file) :: previous_source_files)
-    with Not_found_s _ | Caml.Not_found ->
-      (* Most common case: there is no conflict with the base name of the source file *)
-      Singleton current_source_file
     in
     String.Map.set ~key:basename ~data:entry map
 
 
 let add_root_path path roots = String.Set.add roots path
 
-let load_from_verbose_output javac_verbose_out =
+let load_from_verbose_output =
-  let file_in = In_channel.create javac_verbose_out in
   let class_filename_re =
-    Str.regexp
+    Printf.sprintf
-      (Printf.sprintf
       (* the unreadable regexp below captures 3 possible forms:
          1. [wrote DirectoryFileObject[/path/to/classes_out:path/to/File.java]], leaves `path/to/File.java` in match group 2
          2. [wrote RegularFileObject[path/to/File.java]], leaves `path/to/File.java` in match group 5
@@ -96,20 +95,19 @@ let load_from_verbose_output javac_verbose_out =
          4. [wrote path/to/File.java] leaves `path/to/File.java` in match group 6 (from java 11)*)
       "\\[wrote \
        \\(DirectoryFileObject\\[%s:\\(.*\\)\\|\\(\\(Regular\\|Simple\\)FileObject\\[\\(.*\\)\\)\\]\\|\\(.*\\)\\)\\]"
-         Config.javac_classes_out)
+      Config.javac_classes_out
+    |> Str.regexp
   in
   let source_filename_re =
     Str.regexp "\\[parsing started \\(Regular\\|Simple\\)FileObject\\[\\(.*\\)\\]\\]"
   in
   let classpath_re = Str.regexp "\\[search path for class files: \\(.*\\)\\]" in
-  let rec loop paths roots sources classes =
+  let rec loop paths roots sources classes file_in =
-    match In_channel.input_line_exn file_in with
+    match In_channel.input_line file_in with
-    | exception End_of_file ->
+    | None ->
-        In_channel.close file_in ;
         let classpath = classpath_of_paths (String.Set.elements roots @ paths) in
         {classpath; sources; classes}
-    | line ->
+    | Some line when Str.string_match class_filename_re line 0 -> (
-        if Str.string_match class_filename_re line 0 then
         let path =
           try Str.matched_group 5 line
           with Caml.Not_found -> (
@@ -120,24 +118,27 @@ let load_from_verbose_output javac_verbose_out =
         in
         match Javalib.extract_class_name_from_file path with
         | exception (JBasics.Class_structure_error _ | Invalid_argument _) ->
-              (loop [@tailcall]) paths roots sources classes
+            loop paths roots sources classes file_in
         | cn, root_info ->
             let root_dir =
               if String.equal root_info "" then Filename.current_dir_name else root_info
             in
-              (loop [@tailcall]) paths (add_root_path root_dir roots) sources
+            loop paths (add_root_path root_dir roots) sources (JBasics.ClassSet.add cn classes)
-                (JBasics.ClassSet.add cn classes)
+              file_in )
-        else if Str.string_match source_filename_re line 0 then
+    | Some line when Str.string_match source_filename_re line 0 ->
         let path = Str.matched_group 2 line in
-          (loop [@tailcall]) paths roots (add_source_file path sources) classes
+        loop paths roots (add_source_file path sources) classes file_in
-        else if Str.string_match classpath_re line 0 then
+    | Some line when Str.string_match classpath_re line 0 ->
         let classpath = Str.matched_group 1 line in
         let parsed_paths = String.split ~on:',' classpath in
-          (loop [@tailcall]) parsed_paths roots sources classes
+        loop parsed_paths roots sources classes file_in
-        else (* skip this line *)
+    | _ ->
-          (loop [@tailcall]) paths roots sources classes
+        (* skip this line *)
+        loop paths roots sources classes file_in
   in
-  loop [] String.Set.empty String.Map.empty JBasics.ClassSet.empty
+  fun javac_verbose_out ->
+    Utils.with_file_in javac_verbose_out
+      ~f:(loop [] String.Set.empty String.Map.empty JBasics.ClassSet.empty)
 
 
 let collect_classnames init jar_filename =
@@ -187,6 +188,7 @@ let load_from_arguments classes_out_path =
   let roots, classes = search_classes classes_out_path in
   let split cp_option = Option.value_map ~f:split_classpath ~default:[] cp_option in
   let classpath =
+    (* order follows https://docs.oracle.com/javase/7/docs/technotes/tools/windows/classpath.html *)
     split Config.bootclasspath @ split Config.classpath @ String.Set.elements roots
     |> classpath_of_paths
   in

infer/src/java/jMain.ml

@@ -89,18 +89,18 @@ let do_all_files sources program =
     is_path_matching (SourceFile.to_rel_path source_file)
     || Inferconfig.skip_translation_matcher source_file Procname.empty_block
   in
-  let translate_source_file basename (package_opt, _) source_file =
+  let translate_source_file basename package_opt source_file =
     if not (skip source_file) then do_source_file program tenv basename package_opt source_file
   in
   String.Map.iteri
     ~f:(fun ~key:basename ~data:file_entry ->
       match file_entry with
       | JClasspath.Singleton source_file ->
-          translate_source_file basename (None, source_file) source_file
+          translate_source_file basename None source_file
       | JClasspath.Duplicate source_files ->
           List.iter
             ~f:(fun (package, source_file) ->
-              translate_source_file basename (Some package, source_file) source_file )
+              translate_source_file basename (Some package) source_file )
             source_files )
     sources ;
   if Config.dependency_mode then capture_libs program tenv ;