userdiff: extend Bash pattern to cover more shell function forms

The previous function regex required explicit matching of function
bodies using `{`, `(`, `((`, or `[[`, which caused several issues:

- It failed to capture valid functions where `{` was on the next line
  due to line continuation (`\`).
- It did not recognize functions with single  command body, such as
  `x () echo hello`.

Replacing the function body matching logic with `.*$`, ensures
that everything on the function definition line is captured.

Additionally, the word regex is refined to better recognize shell
syntax, including additional parameter expansion operators and
command-line options.

Signed-off-by: Moumita Dhar <dhar61595@gmail.com>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/t/t4034/bash/pre b/t/t4034/bash/pre
new file mode 100644
index 0000000000..8d22039c40
--- /dev/null
+++ b/t/t4034/bash/pre
@@ -0,0 +1,31 @@
+my_var=10
+x=123
+echo $1
+echo $USER
+${HOME}
+((a+b))
+((a*b))
+((a/b))
+((a%b))
+((a|b))
+((a^b))
+((a=b))
+((a!b))
+((a<b))
+((a>b))
+$((a<b))
+$((a>b))
+$((a&b))
+$((a|b))
+${a:b}
+${a:b}
+${a:b}
+${a:b}
+${a#*/}
+${a%.*}
+${a^}
+${a,}
+${a}
+${a[*]}
+ls -a
+ls --all