[PR] Add silence support.

Summary:
With this patch there is a new section in `.flowconfig`:

```ini
[silence]
/path/to/file.js
/path/to/dir
```

Paths in `[silence]` will still be typechecked, but any
errors will be silenced as if there was a `suppress_comment` comment string
on every line where there are errors.

I called it `silence` to make it stand out from `ignore` and `suppress_comment` as
it currently silences all errors, including lints.

I believe this fixes #869, though I admit I didn't read
the whole issue.

(If this is accepted I'll add docs in a follow-up).
Closes #4916

Reviewed By: mroch

Differential Revision: D8172236

Pulled By: mrkev

fbshipit-source-id: 1ce6771d0065dc42070fee3aa472cf0e760d8dad

src/commands/commandUtils.ml

@@ -382,6 +382,7 @@ let assert_version flowconfig =
 type flowconfig_params = {
   ignores: string list;
   untyped: string list;
+  declarations: string list;
   includes: string list;
   libs: string list;
   (* We store raw_lint_severities as a string list instead of as a LintSettings.t so we
@@ -394,13 +395,14 @@ let list_of_string_arg = function
 | None -> []
 | Some arg_str -> Str.split (Str.regexp ",") arg_str
 
-let collect_flowconfig_flags main ignores_str untyped_str includes_str lib_str lints_str =
+let collect_flowconfig_flags main ignores_str untyped_str declarations_str includes_str lib_str lints_str =
   let ignores = list_of_string_arg ignores_str in
   let untyped = list_of_string_arg untyped_str in
+  let declarations = list_of_string_arg declarations_str in
   let includes = list_of_string_arg includes_str in
   let libs = list_of_string_arg lib_str in
   let raw_lint_severities = list_of_string_arg lints_str in
-  main { ignores; includes; libs; raw_lint_severities; untyped; }
+  main { ignores; includes; libs; raw_lint_severities; untyped; declarations; }
 
 let file_options =
   let default_lib_dir ~no_flowlib tmp_dir =
@@ -466,7 +468,7 @@ let file_options =
     | [] -> config_libs
     | _ -> config_libs @ (List.map (Files.make_path_absolute root) extras)
   in
-  fun ~root ~no_flowlib ~temp_dir ~includes ~ignores ~libs ~untyped flowconfig ->
+  fun ~root ~no_flowlib ~temp_dir ~includes ~ignores ~libs ~untyped ~declarations flowconfig ->
     let default_lib_dir =
       let no_flowlib = no_flowlib || FlowConfig.no_flowlib flowconfig in
       Some (default_lib_dir ~no_flowlib temp_dir)
@@ -479,6 +481,10 @@ let file_options =
       root
       (FlowConfig.untyped flowconfig)
       untyped in
+    let declarations = ignores_of_arg
+      root
+      (FlowConfig.declarations flowconfig)
+      declarations in
     let lib_paths = lib_paths ~root flowconfig libs in
     let includes =
       includes
@@ -488,6 +494,7 @@ let file_options =
       default_lib_dir;
       ignores;
       untyped;
+      declarations;
       includes;
       lib_paths;
       module_file_exts = FlowConfig.module_file_exts flowconfig;
@@ -507,6 +514,12 @@ let untyped_flag prev = CommandSpec.ArgSpec.(
     ~doc:"Specify one or more patterns, comma separated, for files to treat as untyped"
 )
 
+let declaration_flag prev = CommandSpec.ArgSpec.(
+  prev
+  |> flag "--declaration" (optional string)
+    ~doc:"Specify one or more patterns, comma separated, for files to treat as declarations"
+)
+
 let include_flag prev = CommandSpec.ArgSpec.(
   prev
   |> flag "--include" (optional string)
@@ -536,6 +549,7 @@ let flowconfig_flags prev = CommandSpec.ArgSpec.(
   |> collect collect_flowconfig_flags
   |> ignore_flag
   |> untyped_flag
+  |> declaration_flag
   |> include_flag
   |> lib_flag
   |> lints_flag
@@ -793,8 +807,9 @@ let make_options ~flowconfig ~lazy_mode ~root (options_flags: Options_flags.t) =
       libs;
       raw_lint_severities=_;
       untyped;
+      declarations;
     } = options_flags.flowconfig_flags in
-    file_options ~root ~no_flowlib ~temp_dir ~includes ~ignores ~libs ~untyped flowconfig
+    file_options ~root ~no_flowlib ~temp_dir ~includes ~ignores ~libs ~untyped ~declarations flowconfig
   in
   let lint_severities = parse_lints_flag
     (FlowConfig.lint_severities flowconfig) options_flags.flowconfig_flags.raw_lint_severities

src/commands/config/flowConfig.ml

@@ -315,6 +315,8 @@ type config = {
   ignores: string list;
   (* files that should be treated as untyped *)
   untyped: string list;
+  (* files that should be treated as declarations *)
+  declarations: string list;
   (* non-root include paths *)
   includes: string list;
   (* library paths. no wildcards *)
@@ -341,6 +343,9 @@ end = struct
   let untyped o untyped =
     List.iter (fun ex -> (fprintf o "%s\n" ex)) untyped
 
+  let declarations o declarations =
+    List.iter (fun ex -> (fprintf o "%s\n" ex)) declarations
+
   let includes o includes =
     List.iter (fun inc -> (fprintf o "%s\n" inc)) includes
 
@@ -402,6 +407,7 @@ end = struct
     ignores o config.ignores;
     fprintf o "\n";
     section_if_nonempty o "untyped" untyped config.untyped;
+    section_if_nonempty o "declarations" declarations config.declarations;
     section_header o "include";
     includes o config.includes;
     fprintf o "\n";
@@ -421,6 +427,7 @@ end
 let empty_config = {
   ignores = [];
   untyped = [];
+  declarations = [];
   includes = [];
   libs = [];
   lint_severities = LintSettings.empty_severities;
@@ -474,6 +481,10 @@ let parse_untyped config lines =
   let untyped = trim_lines lines in
   { config with untyped; }
 
+let parse_declarations config lines =
+  let declarations = trim_lines lines in
+  { config with declarations; }
+
 let parse_options config lines =
   let open Opts in
   let (>>=) = Core_result.(>>=) in
@@ -959,6 +970,7 @@ let parse_section config ((section_ln, section), lines) =
   | "ignore", _ -> parse_ignores config lines
   | "libs", _ -> parse_libs config lines
   | "lints", _ -> parse_lints config lines
+  | "declarations", _ -> parse_declarations config lines
   | "strict", _ -> parse_strict config lines
   | "options", _ -> parse_options config lines
   | "untyped", _ -> parse_untyped config lines
@@ -1003,15 +1015,17 @@ let read filename =
   } in
   parse config lines, hash
 
-let init ~ignores ~untyped ~includes ~libs ~options ~lints =
+let init ~ignores ~untyped ~declarations ~includes ~libs ~options ~lints =
   let ignores_lines = List.map (fun s -> (1, s)) ignores in
   let untyped_lines = List.map (fun s -> (1, s)) untyped in
+  let declarations_lines = List.map (fun s -> (1, s)) declarations in
   let includes_lines = List.map (fun s -> (1, s)) includes in
   let options_lines = List.map (fun s -> (1, s)) options in
   let lib_lines = List.map (fun s -> (1, s)) libs in
   let lint_lines = List.map (fun s -> (1, s)) lints in
   let config = parse_ignores empty_config ignores_lines in
   let config = parse_untyped config untyped_lines in
+  let config = parse_declarations config declarations_lines in
   let config = parse_includes config includes_lines in
   let config = parse_options config options_lines in
   let config = parse_libs config lib_lines in
@@ -1048,6 +1062,8 @@ let get_hash ?allow_cache filename =
 let ignores config = config.ignores
 (* files that should be treated as untyped *)
 let untyped config = config.untyped
+(* files that should be treated as declarations *)
+let declarations config = config.declarations
 (* non-root include paths *)
 let includes config = config.includes
 (* library paths. no wildcards *)

src/commands/config/flowConfig.mli

@@ -14,6 +14,7 @@ val empty_config: config
 val init:
   ignores: string list ->
   untyped: string list ->
+  declarations: string list ->
   includes: string list ->
   libs: string list ->
   options: string list ->
@@ -27,6 +28,8 @@ val write: config -> out_channel -> unit
 val ignores: config -> string list
 (* files that should be treated as untyped *)
 val untyped: config -> string list
+(* files that should be treated as declarations *)
+val declarations: config -> string list
 (* non-root include paths *)
 val includes: config -> string list
 (* library paths. no wildcards *)

src/commands/genFlowFilesCommand.ml

@@ -56,6 +56,7 @@ let spec = {
     |> ignore_flag
     |> include_flag
     |> untyped_flag
+    |> declaration_flag
     |> from_flag
     |> anon "src" (required string)
     |> flag "--out-dir" string
@@ -85,7 +86,7 @@ let write_file strip_root root content perm src_file_path dest_file_path =
   Unix.close fd
 
 let main option_values root error_flags strip_root ignore_flag
-  include_flag untyped_flag from src out_dir () = (
+  include_flag untyped_flag declaration_flag from src out_dir () = (
   FlowEventLogger.set_from from;
   let src = expand_path src in
   let root = guess_root (
@@ -111,7 +112,7 @@ let main option_values root error_flags strip_root ignore_flag
         FlowExitStatus.exit ~msg FlowExitStatus.Commandline_usage_error
       );
 
-      let options = LsCommand.make_options ~root ~ignore_flag ~include_flag ~untyped_flag in
+      let options = LsCommand.make_options ~root ~ignore_flag ~include_flag ~untyped_flag ~declaration_flag in
       let _, libs = Files.init options in
       let next_files =
         LsCommand.get_ls_files ~root ~all:false ~options ~libs ~imaginary:false (Some src)

src/commands/initCommand.ml

@@ -50,6 +50,7 @@ let main from flowconfig_flags options root () =
   in
   let ignores = flowconfig_flags.CommandUtils.ignores in
   let untyped = flowconfig_flags.CommandUtils.untyped in
+  let declarations = flowconfig_flags.CommandUtils.declarations in
   let includes = flowconfig_flags.CommandUtils.includes in
   let libs = flowconfig_flags.CommandUtils.libs in
   let lints = flowconfig_flags.CommandUtils.raw_lint_severities in
@@ -61,7 +62,7 @@ let main from flowconfig_flags options root () =
     FlowExitStatus.(exit ~msg Invalid_flowconfig)
   end;
 
-  let config = FlowConfig.init ~ignores ~untyped ~includes ~libs ~options ~lints in
+  let config = FlowConfig.init ~ignores ~untyped ~declarations ~includes ~libs ~options ~lints in
 
   let out = Sys_utils.open_out_no_fail file in
   FlowConfig.write config out;

src/commands/lsCommand.ml

@@ -26,6 +26,7 @@ let spec = {
     |> ignore_flag
     |> include_flag
     |> untyped_flag
+    |> declaration_flag
     |> root_flag
     |> json_flags
     |> from_flag
@@ -106,15 +107,16 @@ let rec iter_get_next ~f get_next =
       List.iter f result;
       iter_get_next ~f get_next
 
-let make_options ~root ~ignore_flag ~include_flag ~untyped_flag =
+let make_options ~root ~ignore_flag ~include_flag ~untyped_flag ~declaration_flag =
   let flowconfig = FlowConfig.get (Server_files_js.config_file root) in
   let temp_dir = FlowConfig.temp_dir flowconfig in
   let includes = CommandUtils.list_of_string_arg include_flag in
   let ignores = CommandUtils.list_of_string_arg ignore_flag in
   let untyped = CommandUtils.list_of_string_arg untyped_flag in
+  let declarations = CommandUtils.list_of_string_arg declaration_flag in
   let libs = [] in
   CommandUtils.file_options flowconfig
-    ~root ~no_flowlib:true ~temp_dir ~ignores ~includes ~libs ~untyped
+    ~root ~no_flowlib:true ~temp_dir ~ignores ~includes ~libs ~untyped ~declarations
 
 (* The problem with Files.wanted is that it says yes to everything except ignored files and libs.
  * So implicitly ignored files (like files in another directory) pass the Files.wanted check *)
@@ -174,7 +176,7 @@ let get_next_append_const get_next const =
       ret
 
 let main
-  strip_root ignore_flag include_flag untyped_flag root_flag json pretty from all imaginary reason
+  strip_root ignore_flag include_flag untyped_flag declaration_flag root_flag json pretty from all imaginary reason
   input_file root_or_files () =
 
   let files_or_dirs = get_filenames_from_input ~allow_imaginary:true input_file root_or_files in
@@ -194,7 +196,7 @@ let main
       | _ -> None)
   ) in
 
-  let options = make_options ~root ~ignore_flag ~include_flag ~untyped_flag in
+  let options = make_options ~root ~ignore_flag ~include_flag ~untyped_flag ~declaration_flag in
   (* Turn on --no-flowlib by default, so that flow ls never reports flowlib files *)
   let options = { options with Files.default_lib_dir = None; } in
   let _, libs = Files.init options in

src/common/files.ml

@@ -11,6 +11,7 @@ type options = {
   default_lib_dir: Path.t option;
   ignores: (string * Str.regexp) list;
   untyped: (string * Str.regexp) list;
+  declarations: (string * Str.regexp) list;
   includes: Path_matcher.t;
   lib_paths: Path.t list;
   module_file_exts: SSet.t;
@@ -21,6 +22,7 @@ type options = {
 let default_lib_dir options = options.default_lib_dir
 let ignores options = options.ignores
 let untyped options = options.untyped
+let declarations options = options.declarations
 let includes options = options.includes
 let lib_paths options = options.lib_paths
 let module_file_exts options = options.module_file_exts
@@ -332,6 +334,15 @@ let is_untyped (options: options) =
     let path = Sys_utils.normalize_filename_dir_sep path in
     List.exists (fun rx -> Str.string_match rx path 0) list
 
+(* true if a file path matches a [declarations] entry in config *)
+let is_declaration (options: options) =
+  let list = List.map snd options.declarations in
+  fun path ->
+    (* On Windows, the path may use \ instead of /, but let's standardize the
+     * ignore regex to use / *)
+    let path = Sys_utils.normalize_filename_dir_sep path in
+    List.exists (fun rx -> Str.string_match rx path 0) list
+
 (* true if a file path matches an [include] path in config *)
 let is_included options f =
   Path_matcher.matches options.includes f

src/common/files.mli

@@ -11,6 +11,7 @@ type options = {
   default_lib_dir: Path.t option;
   ignores: (string * Str.regexp) list;
   untyped: (string * Str.regexp) list;
+  declarations: (string * Str.regexp) list;
   includes: Path_matcher.t;
   lib_paths: Path.t list;
   module_file_exts: SSet.t;
@@ -21,6 +22,7 @@ type options = {
 val default_lib_dir: options -> Path.t option
 val ignores: options -> (string * Str.regexp) list
 val untyped: options -> (string * Str.regexp) list
+val declarations: options -> (string * Str.regexp) list
 val includes: options -> Path_matcher.t
 val lib_paths: options -> Path.t list
 val module_file_exts: options -> SSet.t
@@ -42,6 +44,8 @@ val is_flow_file: options: options -> string -> bool
 val is_ignored: options -> string -> bool
 (* true if a file path matches an [untyped] entry in config *)
 val is_untyped: options -> string -> bool
+(* true if a file path matches a [declarations] entry in config *)
+val is_declaration: options -> string -> bool
 (* true if a file path matches an [include] path in config *)
 val is_included: options -> string -> bool
 

src/flow_dot_js.ml

@@ -77,7 +77,7 @@ let load_lib_files ~master_cx ~metadata files
         let cx = Context.make sig_cx metadata lib_file Files.lib_module_ref in
         Flow_js.mk_builtins cx;
         let syms = Type_inference_js.infer_lib_file cx ast
-          ~exclude_syms ~file_sig ~lint_severities:LintSettings.empty_severities
+          ~exclude_syms ~file_sig ~lint_severities:LintSettings.empty_severities ~file_options:None
         in
 
         Context.merge_into (Context.sig_cx master_cx) sig_cx;
@@ -204,7 +204,7 @@ let infer_and_merge ~root filename ast file_sig =
   let strict_mode = StrictModeSettings.empty in
   let file_sigs = Utils_js.FilenameMap.singleton filename file_sig in
   let cx, _other_cxs = Merge_js.merge_component_strict
-    ~metadata ~lint_severities ~strict_mode ~file_sigs
+    ~metadata ~lint_severities ~file_options:None ~strict_mode ~file_sigs
     ~get_ast_unsafe:(fun _ -> ast)
     ~get_docblock_unsafe:(fun _ -> stub_docblock)
     (Nel.one filename) reqs [] (Context.sig_cx master_cx)

src/services/inference/init_js.ml

@@ -74,6 +74,7 @@ let load_lib_files ~master_cx ~options files =
 
         let lib_file = File_key.LibFile file in
         let lint_severities = options.Options.opt_lint_severities in
+        let file_options = Options.file_options options in
         let%lwt result = parse_lib_file options file in
         Lwt.return (match result with
         | Parsing.Parse_ok (ast, file_sig) ->
@@ -89,7 +90,7 @@ let load_lib_files ~master_cx ~options files =
           Flow.mk_builtins cx;
 
           let syms = Infer.infer_lib_file cx ast
-            ~exclude_syms ~lint_severities ~file_sig
+            ~exclude_syms ~lint_severities ~file_options:(Some file_options) ~file_sig
           in
 
           Context.merge_into (Context.sig_cx master_cx) sig_cx;

src/services/inference/merge_service.ml

@@ -99,9 +99,10 @@ let merge_strict_context ~options component =
 
   let metadata = Context.metadata_of_options options in
   let lint_severities = Options.lint_severities options in
+  let file_options = Some (Options.file_options options) in
   let strict_mode = Options.strict_mode options in
   let cx, other_cxs = Merge_js.merge_component_strict
-    ~metadata ~lint_severities ~strict_mode ~file_sigs
+    ~metadata ~lint_severities ~file_options ~strict_mode ~file_sigs
     ~get_ast_unsafe:Parsing_service_js.get_ast_unsafe
     ~get_docblock_unsafe:Parsing_service_js.get_docblock_unsafe
     ~do_gc:(Options.is_debug_mode options)
@@ -140,9 +141,10 @@ let merge_contents_context options file ast info file_sig ~ensure_checked_depend
 
     let metadata = Context.metadata_of_options options in
     let lint_severities = Options.lint_severities options in
+    let file_options = Some (Options.file_options options) in
     let strict_mode = Options.strict_mode options in
     let cx, _ = Merge_js.merge_component_strict
-      ~metadata ~lint_severities ~strict_mode ~file_sigs
+      ~metadata ~lint_severities ~file_options ~strict_mode ~file_sigs
       ~get_ast_unsafe:(fun _ -> ast)
       ~get_docblock_unsafe:(fun _ -> info)
       component file_reqs dep_cxs master_cx