Merge pull request #2 from dmbaturin/T4421

T4421: add support for floating point number in the numeric validator

2 files changed, 35 insertions, 21 deletions

diff --git a/debian/rules b/debian/rules
index e3462af..c6e8920 100755
--- a/debian/rules
+++ b/debian/rules
@@ -8,7 +8,7 @@ DIR := debian/tmp
 override_dh_auto_build:
 	eval `opam env`
 	mkdir -p _build
-	ocamlfind ocamlopt -o _build/numeric -package num -linkpkg src/numeric.ml
+	ocamlfind ocamlopt -o _build/numeric -package pcre -linkpkg src/numeric.ml
 	ocamlfind ocamlopt -o _build/validate-value -package pcre,unix,containers -linkpkg src/validate_value.ml
 
 override_dh_auto_install:
diff --git a/src/numeric.ml b/src/numeric.ml
index 17fcac6..b296cec 100644
--- a/src/numeric.ml
+++ b/src/numeric.ml
@@ -1,23 +1,17 @@
 type options = {
   positive: bool;
   nonnegative: bool;
+  allow_float: bool;
   ranges: string list;
 }
 
 let default_opts = {
   positive = false;
   nonnegative = false;
+  allow_float = false;
   ranges = []
 }
 
-let int_of_string = Big_int.big_int_of_string
-let int_of_string_opt = Big_int.big_int_of_string_opt
-let big = Big_int.big_int_of_int
-let (>=) = Big_int.ge_big_int
-let (<=) = Big_int.le_big_int
-let (<) = Big_int.lt_big_int
-let (>) = Big_int.gt_big_int
-
 let opts = ref default_opts
 
 let number_arg = ref ""
@@ -26,6 +20,7 @@ let args = [
     ("--non-negative", Arg.Unit (fun () -> opts := {!opts with nonnegative=true}), "Check if the number is non-negative (>= 0)");
     ("--positive", Arg.Unit (fun () -> opts := {!opts with positive=true}), "Check if the number is positive (> 0)");
     ("--range", Arg.String (fun s -> let optsv = !opts in opts := {optsv with ranges=(s :: optsv.ranges)}), "Check if the number is within a range (inclusive)");
+    ("--float", Arg.Unit (fun () -> opts := {!opts with allow_float=true}), "Allow floating-point numbers");
 ]
 let usage = Printf.sprintf "Usage: %s [OPTIONS] <number>" Sys.argv.(0)
 
@@ -33,25 +28,44 @@ let () = if Array.length Sys.argv = 1 then (Arg.usage args usage; exit 1)
 let () = Arg.parse args (fun s -> number_arg := s) usage
 
 let check_nonnegative opts n =
-  if opts.nonnegative && (n < (big 0)) then
+  if opts.nonnegative && (n < 0.0) then
   failwith "Number should be non-negative."
 
 let check_positive opts n =
-  if opts.positive && (n <= (big 0)) then
+  if opts.positive && (n <= 0.0) then
   failwith "Number should be positive"
 
-let number_of_string s =
-  let n = int_of_string_opt s in
+let looks_like_number value =
+  try let _ = Pcre.exec ~pat:"^(\\-?)[0-9]+(\\.[0-9]+)?$" value in true
+  with Not_found -> false
+
+let number_of_string opts s =
+  if not (looks_like_number s) then Printf.ksprintf failwith "'%s' is not a valid number" s else
+  let n = float_of_string_opt s in
   match n with
-  | Some n -> n
+  | Some n ->
+    (* If floats are explicitly allowed, just return the number. *)
+    if opts.allow_float then n
+    (* If floats are not explicitly allowed, check if the argument has a decimal separator in it.
+       If the argument string contains a dot but float_of_string didn't dislike it,
+       it's a valid number but not an integer.
+     *)
+    else if not (String.contains s '.') then n
+    (* If float_of_string returned None, the argument string is just garbage rather than a number. *)
+    else Printf.ksprintf failwith "'%s' is not a valid integer number" s
   | None ->
-     Printf.ksprintf failwith "'%s' is not a valid integer number" s
+     Printf.ksprintf failwith "'%s' is not a valid number" s
 
-let range_of_string s =
-  let rs = String.split_on_char '-' s |> List.map String.trim |> List.map int_of_string_opt in
+let range_of_string opts s =
+  let rs = String.split_on_char '-' s |> List.map String.trim |> List.map (number_of_string opts) in
   match rs with
-  | [Some l; Some r] -> (l, r)
-  | _ -> Printf.ksprintf failwith "'%s' is not a valid number range" s
+  | [l; r] -> (l, r)
+  | exception (Failure msg) ->
+    (* Some of the numbers in the range are bad. *)
+    Printf.ksprintf failwith "'%s' is not a valid number range: %s" s msg
+  | _ ->
+    (* The range itself if malformed, like 1-10-20. *)
+    Printf.ksprintf failwith "'%s' is not a valid number range" s
 
 let check_ranges ranges n =
   let in_range (l, r) n = (n >= l) && (n <= r) in
@@ -61,11 +75,11 @@ let check_ranges ranges n =
 
 let () = try
   let opts = !opts in
-  let n = number_of_string !number_arg in
+  let n = number_of_string opts !number_arg in
   check_nonnegative opts n;
   check_positive opts n;
   if opts.ranges <> [] then
-    let ranges = List.map range_of_string opts.ranges in
+    let ranges = List.map (range_of_string opts) opts.ranges in
     check_ranges ranges n
 with (Failure err) ->
   print_endline err;