glsl/glcpp: Add testing for EOF sans newline (and fix for <DEFINE>, <COMMENT>)

The glcpp implementation has long had code to support a file that ends without
a final newline. But we didn't have a "make check" test for this.

Additionally, the <EOF> action was restricted only to the <INITIAL> state so
it would fail to get invoked if the EOF was encountered in the <COMMENT> or
the <DEFINE> case. Neither of these was a bug, per se, since EOF in either
of these cases is an error anyway, (either "unterminated comment" or
"missing macro name for #define").

But with the new explicit support for these cases, we not generate clean error
messages in these cases, (rather than "unexpected $end" from before).

Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

src/glsl/glcpp/glcpp-lex.l

@@ -398,8 +398,11 @@ HEXADECIMAL_INTEGER	0[xX][0-9a-fA-F]+[uU]?
 	return NEWLINE;
 }
 
-	/* Handle missing newline at EOF. */
-<INITIAL><<EOF>> {
+<INITIAL,COMMENT,DEFINE><<EOF>> {
+	if (YY_START == COMMENT)
+		glcpp_error(yylloc, yyextra, "Unterminated comment");
+	if (YY_START == DEFINE)
+		glcpp_error(yylloc, yyextra, "#define without macro name");
 	BEGIN DONE; /* Don't keep matching this rule forever. */
 	yyextra->lexing_directive = 0;
 	return NEWLINE;

src/glsl/glcpp/tests/131-eof-without-newline.c

@@ -0,0 +1 @@
+this file ends with no newline

src/glsl/glcpp/tests/131-eof-without-newline.c.expected

@@ -0,0 +1 @@
+this file ends with no newline

src/glsl/glcpp/tests/132-eof-without-newline-define.c

@@ -0,0 +1 @@
+#define 

src/glsl/glcpp/tests/132-eof-without-newline-define.c.expected

@@ -0,0 +1,2 @@
+0:1(2): preprocessor error: #define without macro name
+0:1(2): preprocessor error: syntax error, unexpected NEWLINE, expecting FUNC_IDENTIFIER or OBJ_IDENTIFIER

src/glsl/glcpp/tests/133-eof-without-newline-comment.c

@@ -0,0 +1 @@
+This file ends with no newline within a comment /* 

src/glsl/glcpp/tests/133-eof-without-newline-comment.c.expected

@@ -0,0 +1,2 @@
+0:1(52): preprocessor error: Unterminated comment
+This file ends with no newline within a comment