[PATCH 1/5] apply: introduce `ignore_ws_default`

["Rubén Justo" <rjusto@gmail.com>]

When we see `--whitespace=fix` we don't consider a possible
option: `--no-ignore-whitespace`.

The expected result in the following example is a failure when
applying the patch, however:

    $ printf "a \nb\nc\n" >file
    $ git add file
    $ cat >patch <<END
    --- a/file
    +++ b/file
    @@ -1,3 +1,2 @@
     a
    -b
     c
    END
    $ git apply --no-ignore-whitespace --whitespace=fix patch
    $ xxd file
    00000000: 610a 630a                                a.c.

This unexpected result will be addressed in an upcoming commit.

As a preparation, we need to detect when the user has explicitly
said `--no-ignore-whitespace`.

Let's add a new value: `ignore_ws_default`, and use it to initialize
`ws_ignore_action` in `init_apply_state()`.  This will allow us to
distinguish whether the user has explicitly set any value for
`ws_ignore_action` via `--[no-]ignore-whitespace` or via
`apply.ignoreWhitespace`.

Currently, we only have one explicit consideration for
`ignore_ws_change`, and no, implicit or explicit, considerations for
`ignore_ws_none`.  Therefore, no modification to the existing logic
is required in this step.

Signed-off-by: Rubén Justo <rjusto@gmail.com>
---
 apply.c | 2 +-
 apply.h | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/apply.c b/apply.c
index 6e1060a952..63e58086f1 100644
--- a/apply.c
+++ b/apply.c
@@ -115,7 +115,7 @@ int init_apply_state(struct apply_state *state,
 	state->p_context = UINT_MAX;
 	state->squelch_whitespace_errors = 5;
 	state->ws_error_action = warn_on_ws_error;
-	state->ws_ignore_action = ignore_ws_none;
+	state->ws_ignore_action = ignore_ws_default;
 	state->linenr = 1;
 	string_list_init_nodup(&state->fn_table);
 	string_list_init_nodup(&state->limit_by_name);
diff --git a/apply.h b/apply.h
index cd25d24cc4..201f953a64 100644
--- a/apply.h
+++ b/apply.h
@@ -16,6 +16,7 @@ enum apply_ws_error_action {
 };
 
 enum apply_ws_ignore {
+	ignore_ws_default,
 	ignore_ws_none,
 	ignore_ws_change
 };
-- 
2.46.0.353.g385c909849