Move declare_executable to phase file (#919)

Author: borkaehw

scala/private/phases/phase_declare_executable.bzl

@@ -5,8 +5,11 @@
 #
 load(
     "@io_bazel_rules_scala//scala/private:rule_impls.bzl",
-    "declare_executable",
+    "is_windows",
 )
 
 def phase_declare_executable(ctx, p):
-    return declare_executable(ctx)
+    if (is_windows(ctx)):
+        return ctx.actions.declare_file("%s.exe" % ctx.label.name)
+    else:
+        return ctx.actions.declare_file(ctx.label.name)

scala/private/rule_impls.bzl

@@ -634,7 +634,7 @@ def _jar_path_based_on_java_bin(ctx):
     return jar_path
 
 def write_executable(ctx, executable, rjars, main_class, jvm_flags, wrapper, use_jacoco):
-    if (_is_windows(ctx)):
+    if (is_windows(ctx)):
         return write_executable_windows(ctx, executable, rjars, main_class, jvm_flags, wrapper, use_jacoco)
     else:
         return write_executable_non_windows(ctx, executable, rjars, main_class, jvm_flags, wrapper, use_jacoco)
@@ -732,12 +732,6 @@ def write_executable_non_windows(ctx, executable, rjars, main_class, jvm_flags,
         )
         return []
 
-def declare_executable(ctx):
-    if (_is_windows(ctx)):
-        return ctx.actions.declare_file("%s.exe" % ctx.label.name)
-    else:
-        return ctx.actions.declare_file(ctx.label.name)
-
 def _collect_runtime_jars(dep_targets):
     runtime_jars = []
 
@@ -885,5 +879,5 @@ def _jacoco_offline_instrument(ctx, input_jar):
 def _jacoco_offline_instrument_format_each(in_out_pair):
     return (["%s=%s" % (in_out_pair[0].path, in_out_pair[1].path)])
 
-def _is_windows(ctx):
+def is_windows(ctx):
     return ctx.configuration.host_path_separator == ";"