more restricted detection of non-use of if_()-like exprs

4 files changed, 33 insertions, 20 deletions

diff --git a/perl_checker.src/flags.ml b/perl_checker.src/flags.ml
index b2c40c2..5256831 100644
--- a/perl_checker.src/flags.ml
+++ b/perl_checker.src/flags.ml
@@ -2,4 +2,3 @@ open Common
 
 let verbose = ref false
 let quiet = ref false
-
diff --git a/perl_checker.src/parser.mly b/perl_checker.src/parser.mly
index 45c0db8..364ab5a 100644
--- a/perl_checker.src/parser.mly
+++ b/perl_checker.src/parser.mly
@@ -233,10 +233,10 @@ term:
 | term PATTERN_MATCH_NOT STRING {die_with_rawpos (sndsnd $3) "use a regexp, not a string"}
 
 
-| term QUESTION_MARK term COLON term {sp_p($2); sp_p($3); sp_p($4); sp_p($5); check_ternary_paras $3 $5; to_Call_op_(P_ternary, "?:", [ prio_lo P_ternary $1 ; prio_lo_after P_ternary $3; prio_lo_after P_ternary $5]) (sp_pos_range $1 $5)}
-| term QUESTION_MARK term COLON BRACKET expr BRACKET_END {sp_p($2); sp_p($3); check_ternary_para $3; sp_p($4); sp_p($5); sp_p($6); sp_p($7); check_ternary_para $1; to_Call_op_(P_ternary, "?:", [ prio_lo P_ternary $1 ; prio_lo_after P_ternary $3; Ref(I_hash, sndfst $6)]) (sp_pos_range $1 $7)}
-| term QUESTION_MARK BRACKET expr BRACKET_END COLON term {sp_p($2); sp_p($3); sp_p($4); sp_p($5); sp_p($6); sp_p($7); check_ternary_para $7; to_Call_op_(P_ternary, "?:", [ prio_lo P_ternary $1 ; Ref(I_hash, sndfst $4); prio_lo_after P_ternary $7]) (sp_pos_range $1 $7)}
-| term QUESTION_MARK BRACKET expr BRACKET_END COLON BRACKET expr BRACKET_END {sp_p($2); sp_p($3); sp_p($4); sp_p($5); sp_p($6); sp_p($7); sp_p($8); sp_p($9); to_Call_op_(P_ternary, "?:", [ prio_lo P_ternary $1 ; Ref(I_hash, sndfst $4); Ref(I_hash, sndfst $8)]) (sp_pos_range $1 $9)}
+| term QUESTION_MARK term COLON term {sp_p($2); sp_p($3); sp_p($4); sp_p($5); to_Call_op_(P_ternary, "?:", check_ternary_paras(prio_lo P_ternary $1, prio_lo_after P_ternary $3, prio_lo_after P_ternary $5)) (sp_pos_range $1 $5)}
+| term QUESTION_MARK term COLON BRACKET expr BRACKET_END {sp_p($2); sp_p($3); sp_p($4); sp_p($5); sp_p($6); sp_p($7); to_Call_op_(P_ternary, "?:", check_ternary_paras(prio_lo P_ternary $1, prio_lo_after P_ternary $3, Ref(I_hash, sndfst $6))) (sp_pos_range $1 $7)}
+| term QUESTION_MARK BRACKET expr BRACKET_END COLON term {sp_p($2); sp_p($3); sp_p($4); sp_p($5); sp_p($6); sp_p($7); to_Call_op_(P_ternary, "?:", check_ternary_paras(prio_lo P_ternary $1, Ref(I_hash, sndfst $4), prio_lo_after P_ternary $7)) (sp_pos_range $1 $7)}
+| term QUESTION_MARK BRACKET expr BRACKET_END COLON BRACKET expr BRACKET_END {sp_p($2); sp_p($3); sp_p($4); sp_p($5); sp_p($6); sp_p($7); sp_p($8); sp_p($9); to_Call_op_(P_ternary, "?:", check_ternary_paras(prio_lo P_ternary $1, Ref(I_hash, sndfst $4), Ref(I_hash, sndfst $8))) (sp_pos_range $1 $9)}
 
 
 /* Unary operators and terms */
diff --git a/perl_checker.src/parser_helper.ml b/perl_checker.src/parser_helper.ml
index 00b121d..a965dba 100644
--- a/perl_checker.src/parser_helper.ml
+++ b/perl_checker.src/parser_helper.ml
@@ -17,9 +17,6 @@ let is_var_dollar_ = function
 let is_var_number_match = function
   | Deref(I_scalar, Ident(None, s, _)) -> String.length s = 1 && s.[0] <> '0' && char_is_number s.[0]
   | _ -> false
-let is_call = function
-  | Call _ -> true
-  | _ -> false
 
 let is_parenthesized = function
   | List[]
@@ -282,14 +279,33 @@ let check_arrow_needed ((_, e), _) ter =
   | Deref_with _ -> warn (sndsnd ter) "the arrow \"->\" is unneeded"
   | _ -> ()
 
-let check_ternary_para ((_, e), _) =
-  match e with
-  | List [] -> warn_rule "you may use if_() here\n  beware that the short-circuit semantic of ?: is not kept\n  if you want to keep the short-circuit behaviour, replace () with @{[]} and there will be no warning anymore"
-  | _ -> ()
-
-let check_ternary_paras ((_, e1), _ as ter1) ((_, e2), _ as ter2) =
-  if not (is_call e1) then check_ternary_para ter2;
-  if not (is_call e2) then check_ternary_para ter1
+let check_ternary_paras(cond, a, b) =
+  let rec dont_need_short_circuit_rec = function
+    | Num _
+    | Raw_string _
+    | String ([(_, List [])], _) 
+    | Call_op("qw", _, _)
+      -> true
+    | Call(Deref(I_func, Ident(None, "N", _)), [ List(String _ :: l) ])
+    | Call_op(".", l, _)
+    | Ref(I_hash, List l)
+    | List l -> List.for_all dont_need_short_circuit_rec l
+    | _ -> false
+  in
+  let rec dont_need_short_circuit = function
+    | Ref(_, Deref(_, Ident _))
+    | Deref(_, Ident _) -> true
+    | Ref(I_hash, List l)
+    | List l -> List.for_all dont_need_short_circuit l
+    | e -> dont_need_short_circuit_rec e
+  in
+  let check_ternary_para = function
+    | List [] -> warn_rule "you may use if_() here\n  beware that the short-circuit semantic of ?: is not kept\n  if you want to keep the short-circuit behaviour, replace () with @{[]} and there will be no warning anymore"
+    | _ -> ()
+  in
+  if dont_need_short_circuit a || is_same_fromparser cond a then check_ternary_para b;
+  if dont_need_short_circuit b || is_same_fromparser cond b then check_ternary_para a;
+  [ cond; a; b ]
 
 let check_unneeded_var_dollar_    ((_, e), (_, pos)) =
   if is_var_dollar_ e then warn pos "\"$_ =~ /regexp/\" can be written \"/regexp/\"" else
diff --git a/perl_checker.src/parser_helper.mli b/perl_checker.src/parser_helper.mli
index d3f5396..a5b0837 100644
--- a/perl_checker.src/parser_helper.mli
+++ b/perl_checker.src/parser_helper.mli
@@ -9,7 +9,6 @@ val var_dollar_ : Types.fromparser
 val var_STDOUT : Types.fromparser
 val is_var_dollar_ : Types.fromparser -> bool
 val is_var_number_match : Types.fromparser -> bool
-val is_call : Types.fromparser -> bool
 val is_parenthesized : Types.fromparser -> bool
 val un_parenthesize : Types.fromparser -> Types.fromparser
 val un_parenthesize_full : Types.fromparser -> Types.fromparser
@@ -62,10 +61,9 @@ val check_hash_subscript :
   ('a * Types.fromparser) * ('b * (int * int)) -> unit
 val check_arrow_needed :
   ('a * Types.fromparser) * 'b -> 'c * ('d * (int * int)) -> unit
-val check_ternary_para : ('a * Types.fromparser) * ('b * (int * int)) -> unit
 val check_ternary_paras :
-  ('a * Types.fromparser) * ('b * (int * int)) ->
-  ('c * Types.fromparser) * ('d * (int * int)) -> unit
+  Types.fromparser * Types.fromparser * Types.fromparser ->
+  Types.fromparser list
 val check_unneeded_var_dollar_ :
   ('a * Types.fromparser) * ('b * (int * int)) -> unit
 val check_unneeded_var_dollar_not :