From 419817e65607141997ec2701c672bc2fdd805dc1 Mon Sep 17 00:00:00 2001
From: Vladimir Zhelezov <zhelezov@gmail.com>
Date: Sun, 20 Dec 2020 07:56:47 +0100
Subject: [PATCH] Prevent unwanted m4 macro expansion + `-g` GNU compatibility
 flag

Most of the included files are meant to be output literally, without any
macro processing. Using `undivert` in place of `include` achieves that.
This is a safety net against unsanitized input generated during the
build. Also, developers editing the shell code stub shouldn't be
constantly alert about triggering accidental macro expansion.

In order that `undivert` mimics GNU behaviour on BSDs, the `-g` flag is
used for the m4 invocation.
---
 shell-completion/Makefile                   |  2 +-
 shell-completion/hledger-completion.bash.m4 | 10 +++++-----
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/shell-completion/Makefile b/shell-completion/Makefile
index e61d71066..9c9deccdd 100644
--- a/shell-completion/Makefile
+++ b/shell-completion/Makefile
@@ -63,7 +63,7 @@ $(CMDOPTFILES)
 endef
 
 hledger-completion.bash: $(M4DEPS)
-	m4 hledger-completion.bash.m4 > $@
+	m4 -g hledger-completion.bash.m4 > $@
 
 commands.txt:
 	printf "%s\n" $(COMMANDS) > $@
diff --git a/shell-completion/hledger-completion.bash.m4 b/shell-completion/hledger-completion.bash.m4
index a5636417c..4e4685944 100644
--- a/shell-completion/hledger-completion.bash.m4
+++ b/shell-completion/hledger-completion.bash.m4
@@ -1,19 +1,19 @@
-include(`hledger-completion.bash.stub')dnl
+undivert(`hledger-completion.bash.stub')dnl
 
 # Include lists of commands and options generated by the Makefile using the
 # m4 macro processor.
 # Included files must have exactly one newline at EOF to prevent weired errors.
 
 read -r -d "" _hledger_complist_commands <<TEXT
-include(`commands.txt')dnl
+undivert(`commands.txt')dnl
 TEXT
 
 read -r -d "" _hledger_complist_query_filters <<TEXT
-include(`query-filters.txt')dnl
+undivert(`query-filters.txt')dnl
 TEXT
 
 read -r -d "" _hledger_complist_generic_options <<TEXT
-include(`generic-options.txt')dnl
+undivert(`generic-options.txt')dnl
 TEXT
 
 # Dashes are replaced by m4 with underscores to form valid identifiers
@@ -22,7 +22,7 @@ dnl
 include(`foreach2.m4')dnl
 foreach(`cmd', (include(`commands-list.txt')), `
 read -r -d "" _hledger_complist_options_`'translit(cmd, -, _) <<TEXT
-include(options-cmd.txt)dnl
+undivert(options-cmd.txt)dnl
 TEXT
 ')dnl