From 8cda0a6cc9cc31edf0fe94c470038f12c8dcc905 Mon Sep 17 00:00:00 2001
From: Nick Bowler <nbowler@draconx.ca>
Date: Fri, 17 Jun 2022 21:33:07 -0400
Subject: [PATCH] gen-tree.awk: Allow simple '#' comments.

---
 scripts/gen-tree.awk | 13 +++++++++----
 tests/scripts.at     |  7 +++++--
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/scripts/gen-tree.awk b/scripts/gen-tree.awk
index d04378a..c461e5d 100755
--- a/scripts/gen-tree.awk
+++ b/scripts/gen-tree.awk
@@ -5,9 +5,11 @@
 # Generate one or more C array initializers to encode simple tree structures
 # in a compact format.
 #
-# Each nonempty line of the input file is either an option specification
-# or # a tree specification.  An option specification (described later)
-# begins with an @ character.  Other lines specify tree nodes.
+# Each nonempty line of the input file is either a comment, an option
+# specification or a tree specification.  Each line is distinguished by
+# its first character.  A # character introduces a comment, an @ character
+# introduces an option specification (described later), and all other
+# nonempty lines are tree nodes.
 #
 # The first field of a tree specification must be a valid C identifier,
 # optionally followed by a comma.  The identifiers used on non-leaf nodes
@@ -102,6 +104,10 @@ BEGIN {
   indent_stack[0] = 0;
 }
 
+# Comments
+NF == 0 { next }
+$0 ~ /^#/ { next }
+
 # Options
 sub(/^@/, "", $0) {
   if (NF == 1) {
@@ -118,7 +124,6 @@ sub(/^@/, "", $0) {
   next
 }
 
-NF == 0 { next }
 { indent = index($0, $1) - 1 }
 
 indent > 0 {
diff --git a/tests/scripts.at b/tests/scripts.at
index dcbcce5..41dfbb4 100644
--- a/tests/scripts.at
+++ b/tests/scripts.at
@@ -306,7 +306,8 @@ AT_SETUP([gen-tree.awk])
 AT_KEYWORDS([gen-tree awk script scripts])
 
 AT_DATA([tree.def],
-[[ROOT0
+[[# comment
+ROOT0
   r0a, r0a_OFFSET
     r0b, r0b_OFFSET
       r0c
@@ -314,6 +315,7 @@ AT_DATA([tree.def],
   r0e, r0e_OFFSET
     r0f
     r0g
+# comment
 ROOT1
   r1a, r1a_OFFSET
     r1b, r1b_OFFSET
@@ -325,6 +327,7 @@ ROOT1
       r1e
       r1b
       r1e
+# comment
 ]])
 
 AT_CHECK([$AWK -f "$builddir/scripts/gen-tree.awk" <tree.def >tree.h])
@@ -366,7 +369,7 @@ int main(void)
   return 0;
 }
 ]])
-cp tree.def expout
+sed '/^#/d' tree.def >expout
 AT_CHECK([$CC -o test0$EXEEXT test0.c && ./test0$EXEEXT], [0], [expout])
 
 AT_CLEANUP
-- 
2.43.2