ParseXS: refactor: add POSTCALL node

add this class:

    ExtUtils::ParseXS::Node::POSTCALL

and add a few basic tests for the POSTCALL keyword.

Note that (similarly to other codeblock-derived Node classes), this
commit causes a (harmless) slight change of '#line' output for an empty
code block. In particular, this:

    5: void
    6: foo()
    7:   POSTCALL:
    8:

used to generate these two adjacent lines of C code:

    #line 7 "foo.xs"
    #line NNN "foo.c"

but now outputs:

    #line 8 "foo.xs"
    #line NNN "foo.c"

Author: iabyn

dist/ExtUtils-ParseXS/lib/ExtUtils/ParseXS.pm

@@ -1812,12 +1812,6 @@ sub CLEANUP_handler {
 }
 
 
-sub POSTCALL_handler {
-  my ExtUtils::ParseXS $self = shift;
-  $self->print_section();
-}
-
-
 sub FALLBACK_handler {
   my ExtUtils::ParseXS $self = shift;
   my ($setting) = @_;

dist/ExtUtils-ParseXS/lib/ExtUtils/ParseXS/Node.pm

@@ -2434,6 +2434,18 @@ BEGIN { $build_subclass->('codeblock', # parent
 # Currently all methods are just inherited.
 
 
+# ======================================================================
+
+package ExtUtils::ParseXS::Node::POSTCALL;
+
+# Store the code lines associated with the POSTCALL: keyword
+
+BEGIN { $build_subclass->('codeblock', # parent
+)};
+
+# Currently all methods are just inherited.
+
+
 # ======================================================================
 
 package ExtUtils::ParseXS::Node::PPCODE;

dist/ExtUtils-ParseXS/t/001-basic.t

@@ -4217,4 +4217,46 @@ EOF
 }
 
 
+{
+    # Test POSTCALL keyword
+
+    my $preamble = Q(<<'EOF');
+        |MODULE = Foo PACKAGE = Foo
+        |
+        |PROTOTYPES:  DISABLE
+        |
+EOF
+
+    my @test_fns = (
+        [
+            "POSTCALL basic",
+            [ Q(<<'EOF') ],
+                |int
+                |foo(int aaa)
+                |  POSTCALL:
+                |     YYY
+EOF
+            [ 0, 0, qr{\bint\s+aaa},                  "has aaa decl"      ],
+            [ 0, 0, qr{^\s+\QRETVAL = foo(aaa);}m,    "has code body"     ],
+            [ 0, 0, qr{^\s+YYY\n}m,                   "has postcall body" ],
+            [ 0, 0, qr{aaa.*foo\(aaa\).*YYY.*TARGi}s, "in sequence"       ],
+            [ 0, 0, qr{\#line 8 .*\n\s+YYY},          "correct #line"     ],
+        ],
+        [
+             "POSTCALL empty",
+             [ Q(<<'EOF') ],
+                 |void
+                 |foo(int aaa)
+                 |  POSTCALL:
+EOF
+            [ 0, 0, qr{\bint\s+aaa},                  "has aaa decl"      ],
+            [ 0, 0, qr{^\s+\Qfoo(aaa);}m,             "has code body"     ],
+            [ 0, 0, qr{\Qfoo(aaa);\E\n\#line 8 },     "correct #line"     ],
+         ],
+    );
+
+    test_many($preamble, 'XS_Foo_', \@test_fns);
+}
+
+
 done_testing;