Merge 14976ae into ab583dc

rebar.config

@@ -9,6 +9,11 @@
     {git, "https://github.com/lpgauth/shackle.git", {tag, "0.6.2"}}}
 ]}.
 
+{project_plugins, [
+  {gradualizer,
+    {git, "https://github.com/josefs/gradualizer.git", {tag, "0.1.0"}}}
+]}.
+
 {edoc_opts, [
   {app_default, "http://www.erlang.org/doc/man"},
   {doclet, edown_doclet},
@@ -64,3 +69,8 @@
   locals_not_used,
   undefined_function_calls
 ]}.
+
+{gradualizer_opts, [
+    {i, "include"},
+    print_file
+]}.

src/buoy_app.erl

@@ -14,7 +14,7 @@
 
 %% public
 -spec start() ->
-    {ok, [atom()]}.
+    {ok, [atom()]} | {error, term()}.
 
 start() ->
     application:ensure_all_started(?APP).

src/buoy_pool.erl

@@ -12,7 +12,7 @@
 
 %% public
 -spec init() ->
-    ok.
+    ok | error().
 
 init() ->
     foil:new(?MODULE),
@@ -38,7 +38,7 @@ start(Url) ->
     start(Url, ?DEFAULT_POOL_OPTIONS).
 
 -spec start(buoy_url(), options()) ->
-    ok | {error, pool_already_started | buoy_not_started}.
+    ok | {error, pool_already_started | buoy_not_started} | error().
 
 start(#buoy_url {
         protocol = Protocol,
@@ -62,7 +62,7 @@ start(#buoy_url {
     end.
 
 -spec stop(buoy_url()) ->
-    ok | {error,  pool_not_started | buoy_not_started}.
+    ok | {error,  pool_not_started | buoy_not_started} | error().
 
 stop(#buoy_url {
         protocol = Protocol,
@@ -83,7 +83,7 @@ stop(#buoy_url {
     end.
 
 -spec terminate() ->
-    ok.
+    ok | error().
 
 terminate() ->
     foil:delete(?MODULE).

src/buoy_sup.erl

@@ -11,8 +11,8 @@
 ]).
 
 %% public
--spec start_link() ->
-    {ok, pid()}.
+% Wrong but can't be corrected until OTP exports startlink_ret() (OTP 23)
+% -spec start_link() -> {ok, pid()}.
 
 start_link() ->
     supervisor:start_link({local, ?MODULE}, ?MODULE, []).