fix(pkgbuild.sh): Use grep -Fx to check for pkgrel and pkgver declaration

In order to automatically replace pkgrel and pkgver, we must first check
that they are declared in the usual way as a key-value pair.
If pkgrel or pkgver contain special characters like +, they are currently
interpreted as regex. Use --fixed-strings to instead signify that they should
be literal patterns. Since the declaration must be on its own line and anchors
can't be in literal patterns, also specify --line-regexp to only consider
whole line matches.

Using sed with --extended-regexp fails for a similar reason in that the +
is treated as a special character. As it's only use was to save some
typing (not repeating pkgver= and pkgrel=), remove the option.

Makefile

@@ -1,6 +1,6 @@
 SHELL=/bin/bash -o pipefail
 
-V=1.3.1
+V=1.3.2
 BUILDTOOLVER ?= $(V)
 
 PREFIX = /usr/local

config/makepkg/conf.d/rust.conf

@@ -11,7 +11,7 @@
 
 # Flags used for the Rust compiler, similar in spirit to CFLAGS. Read
 # linkman:rustc[1] for more details on the available flags.
-RUSTFLAGS="-Cforce-frame-pointers=yes"
+RUSTFLAGS="-C force-frame-pointers=yes"
 
 # Additional compiler flags appended to `RUSTFLAGS` for use in debugging.
 # Usually this would include: ``-C debuginfo=2''. Read linkman:rustc[1] for

src/lib/util/pkgbuild.sh

@@ -26,10 +26,10 @@ pkgbuild_set_pkgver() {
 		warning 'setting pkgver variable has no effect if the PKGBUILD has a pkgver() function'
 	fi
 
-	if ! grep --extended-regexp --quiet --max-count=1 "^pkgver=${pkgver}$" PKGBUILD; then
+	if ! grep --fixed-strings --line-regexp --quiet --max-count=1 "pkgver=${pkgver}" PKGBUILD; then
 		die "Non-standard pkgver declaration"
 	fi
-	sed --regexp-extended "s|^(pkgver=)${pkgver}$|\1${new_pkgver}|g" --in-place PKGBUILD
+	sed "s|^pkgver=${pkgver}$|pkgver=${new_pkgver}|g" --in-place PKGBUILD
 }
 
 # set the pkgrel variable in a PKGBUILD
@@ -38,10 +38,10 @@ pkgbuild_set_pkgrel() {
 	local new_pkgrel=$1
 	local pkgrel=${pkgrel}
 
-	if ! grep --extended-regexp --quiet --max-count=1 "^pkgrel=${pkgrel}$" PKGBUILD; then
+	if ! grep --fixed-strings --line-regexp --quiet --max-count=1 "pkgrel=${pkgrel}" PKGBUILD; then
 		die "Non-standard pkgrel declaration"
 	fi
-	sed --regexp-extended "s|^(pkgrel=)${pkgrel}$|\1${new_pkgrel}|g" --in-place PKGBUILD
+	sed "s|^pkgrel=${pkgrel}$|pkgrel=${new_pkgrel}|g" --in-place PKGBUILD
 }
 
 pkgbuild_update_checksums() {