Fix: adjust definition of Location.is_single_line to reflect margin

[jberdine]

This seems to be needed to be consistent with recent changes to the
handling of the margin. Otherwise, it is possible to have a one-liner
structure item of just the right width that is_single_line does not
hold, resulting in the one-liner being surrounded by open lines.

[gpetiot]

Otherwise, it is possible to have a one-liner
structure item of just the right width that is_single_line does not
hold, resulting in the one-liner being surrounded by open lines.

Do you have an example for this?

[jberdine]

Yes, IIRC one is:

val xx_xxxxxxxx : t -> bool
val xxxxxxxx : t -> [> `Xxxxxx | `Xxxxxxxxxxx | `Xxxxxxxxxx | `Xxxxxxxxxxxxx]
val xxxxx : t -> t -> t Xxx.t option

with a margin of 77.

[gpetiot]

I tested it on master, the output of is_single_line is true for each item of this file.

[jberdine]

It seems that module-item-spacing=compact is also needed. I added a test file that should be unchanged, and is with this PR, but isn't on master.

[gpetiot]

val xxxxxxxx : t -> [> Xxxxxxx | Xxxxxxxxxxx | Xxxxxxxxxx | Xxxxxxxxxxxxx] is 88 characters long but it doesn't break, like #1069 (square brackets), we can start by fixing this.

[gpetiot]

I rebased the branch, there is no diff with test_branch except with the janestreet profile:

diff --git a/compiler/num-testsuite/test_big_ints.ml b/compiler/num-testsuite/test_big_ints.ml
index c2390ae3a..2475eb912 100644
--- a/compiler/num-testsuite/test_big_ints.ml
+++ b/compiler/num-testsuite/test_big_ints.ml
@@ -103,10 +103,8 @@ test
 
 ;;
 test 16 eq_big_int (add_big_int (big_int_of_int (-1)) (big_int_of_int 2), big_int_of_int 1)
-
 ;;
 test 17 eq_big_int (add_big_int (big_int_of_int 2) (big_int_of_int (-1)), big_int_of_int 1)
-
 ;;
 testing_function "sub_big_int"
 ;;
@@ -166,7 +164,6 @@ test
 
 ;;
 test 17 eq_big_int (sub_big_int (big_int_of_int 2) (big_int_of_int (-1)), big_int_of_int 3)
-
 ;;
 testing_function "mult_int_big_int"
 ;;
@@ -946,7 +943,6 @@ test
 testing_function "shift_right_big_int"
 ;;
 test 1 eq_big_int (shift_right_big_int unit_big_int 0, unit_big_int)
-
 ;;
 test 2 eq_big_int (shift_right_big_int (big_int_of_int 12345678) 3, big_int_of_int 1543209)
 
diff --git a/compiler/num-testsuite/test_nums.ml b/compiler/num-testsuite/test_nums.ml
index d4fc822a6..469841bcf 100644
--- a/compiler/num-testsuite/test_nums.ml
+++ b/compiler/num-testsuite/test_nums.ml
@@ -97,7 +97,6 @@ test 10 eq_num (sub_num (Int (-1)) (Int biggest_int), pred_num (Int least_int))
 testing_function "mult_num"
 ;;
 test 1 eq_num (mult_num (Int 2) (Int 3), Int 6)
-
 ;;
 test 2 eq_num (mult_num (Int 127) (Int (int_of_string "257")), Int (int_of_string "32639"))
 
diff --git a/compiler/num-testsuite/test_ratios.ml b/compiler/num-testsuite/test_ratios.ml
index 32a8fa7f5..40d53626a 100644
--- a/compiler/num-testsuite/test_ratios.ml
+++ b/compiler/num-testsuite/test_ratios.ml
@@ -74,10 +74,8 @@ test 9 eq_big_int (numerator_ratio r, big_int_of_int 0)
 
 ;;
 testing_function "null_denominator"
-
 ;;
 test 1 eq (null_denominator (create_ratio (big_int_of_int 1) (big_int_of_int (-2))), false)
-
 ;;
 test 2 eq (null_denominator (create_ratio (big_int_of_int 1) zero_big_int), true)

The longer lines of this diff exceed the 90 column margin, but it was already the case in master (related to #1066, #1069). The new output is more consistent since it behaves the same way for every non-breaking lines.
So maybe we can merge it afterall @Julow ?

[Julow]

Looks good to me.