Add command line arguments for reactive mode.

Summary:public
Add command-line argument --reactive to enable reactive propagation mode.
When the mode is active, the files changed during compilation are detected, and the analysis propagates reactively starting from the modified files.
The reactive mode allows to analyze a subset of the files in a project and follow their dependencies, without storing the results of previous analyses (specs files). Captured files are preserved from previous runs of the analysis (for example, when the previous analysis was the initial capture), so the mode can be used repeatedly while changing code.

Reviewed By: jvillard

Differential Revision: D2931697

fb-gh-sync-id: 9d6dda0
shipit-source-id: 9d6dda0

infer/lib/python/infer

@@ -114,6 +114,7 @@ def main():
 
     remove_infer_out = (imported_module
                         and not args.incremental
+                        and not args.reactive
                         and capture_module_name != 'analyze'
                         and not args.buck)
     if remove_infer_out:

infer/lib/python/inferlib/analyze.py

@@ -75,6 +75,9 @@ base_group.add_argument('-ic', '--changed-only',
                         action=ConfirmIncrementalAction,
                         help='''Same as -i, but does not analyze
                         dependencies of changed procedures.''')
+base_group.add_argument('--reactive', action='store_true',
+                        help='''Analyze in reactive propagation mode
+                        starting from changed files.''')
 base_group.add_argument('--debug-exceptions', action='store_true',
                         help='''Generate lightweight debugging information:
                         just print the internal exceptions during analysis''')
@@ -418,6 +421,9 @@ class Infer:
             else:
                 infer_options.append('-incremental')
 
+        if self.args.reactive:
+            infer_options.append('-reactive')
+
         if self.args.specs_dirs:
             infer_options += self.args.specs_dirs
 

infer/src/backend/clusterMakefile.ml

@@ -30,12 +30,29 @@ let pp_prolog fmt clusters =
         begin
           match Cluster.get_ondemand_info ce with
           | Some source_dir ->
-              let in_ondemand_config = match Ondemand.read_dirs_to_analyze () with
+              let fname = DB.source_dir_to_string source_dir in
+              let in_ondemand_config =
+                match Ondemand.read_dirs_to_analyze () with
                 | None ->
-                    true
+                    None
                 | Some set ->
-                    StringSet.mem (DB.source_dir_to_string source_dir) set in
-              in_ondemand_config
+                    Some (StringSet.mem fname set) in
+              let check_modified () =
+                let modified =
+                  DB.file_was_updated_after_start (DB.filename_from_string fname) in
+                if modified &&
+                   !Config.developer_mode
+                then L.stdout "Modified: %s@." fname;
+                modified in
+              begin
+                match in_ondemand_config with
+                | Some b -> (* ondemand config file is specified *)
+                    b
+                | None when !Config.reactive_mode  ->
+                    check_modified ()
+                | None ->
+                    true
+              end
           | None ->
               true
         end

infer/src/backend/config.ml

@@ -179,9 +179,14 @@ let eradicate = ref false
 (** should the checkers be run? *)
 let checkers_enabled () = not !eradicate
 
-(** flag to activate ondemand mode. *)
+(** flag for ondemand mode:
+    procedure calls trigger a new analysis if the summary is not present already *)
 let ondemand_enabled = ref false
 
+(** flag for reactive mode:
+    the analysis starts from the files captured since the "infer" command started *)
+let reactive_mode = ref false
+
 (** Flag for footprint discovery mode *)
 let footprint = ref true
 

infer/src/backend/inferanalyze.ml

@@ -177,6 +177,11 @@ let arg_desc =
         None,
         "print the builtin functions and exit"
         ;
+        "-reactive",
+        Arg.Unit (fun () -> Config.ondemand_enabled := true; Config.reactive_mode := true),
+        None,
+        "analyze in reactive propagation mode starting from changed files"
+        ;
         "-source_path",
         Arg.String source_path,
         Some "path",