libcmd: update to support lowdown-1.4 API

[trofi]

Motivation

Upstream change
kristapsdz/lowdown@bab1d75 moved a few fields from lowdown_opts toa new lowdown_opts_term struct. As a result the build started failing as:

nix-cmd> [2/17] Compiling C++ object libnixcmd.so.p/markdown.cc.o
nix-cmd> FAILED: libnixcmd.so.p/markdown.cc.o
nix-cmd> g++ -Ilibnixcmd.so.p -I. -I.. -I/nix/store/b0bnrk5lacxbpgxgnc28r8q3wcazrgxj-nix-util-2.26.0pre-dev/include/nix -I/nix/store/cxnynq9ykyj4xxv6wf6dw7r0aw5x6n9k-libarchive-3.7.7-dev/include -I/nix/store/bfgjwkcb8snkizx578rzdahi75m8zyh4-nlohmann_json-3.11.3/include -I/nix/store/3sx8bq3sip6j2nv1m5xx4gbdp33v7iy6-nix-store-2.26.0pre-dev/include/nix -I/nix/store/sih2dgqzvsbv7p510lkfmas7s7wbsl4j-nix-fetchers-2.26.0pre-dev/include/nix -I/nix/store/68p8s20fsiiakj7nys7grbaixfnhsdzs-nix-expr-2.26.0pre-dev/include/nix -I/nix/store/gw7wknhzhfzzj9zww2kyi5xrzgf1ndki-boehm-gc-8.2.8-dev/include -I/nix/store/3jwb9j4vnsk5saq3wfyyp9il3mhs41l9-nix-flake-2.26.0pre-dev/include/nix -I/nix/store/8nwjvmq7m48v8g646jrxkikv6x47bc3m-nix-main-2.26.0pre-dev/include/nix -I/nix/store/rb0hzsw5wc1a7daizhpj824mbxlvijrq-lowdown-1.4.0-dev/include -I/nix/store/m388ywpk53fsp8r98brfd7nf1f5sskv0-editline-1.17.1-dev/include -fdiagnostics-color=always -D_GLIBCXX_ASSERTIONS=1 -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch -std=c++2a -include config-util.hh -include config-store.hh -include config-expr.hh -include config-main.hh -include config-cmd.hh -Wdeprecated-copy -Werror=suggest-override -Werror=switch -Werror=switch-enum -Werror=unused-result -Wignored-qualifiers -Wimplicit-fallthrough -Wno-deprecated-declarations -O3 -fPIC -pthread -std=c++2a -std=c++2a -std=c++2a -std=c++2a -std=c++2a -std=c++2a -MD -MQ libnixcmd.so.p/markdown.cc.o -MF libnixcmd.so.p/markdown.cc.o.d -o libnixcmd.so.p/markdown.cc.o -c ../markdown.cc
nix-cmd> ../markdown.cc: In function 'std::string nix::doRenderMarkdownToTerminal(std::string_view)':
nix-cmd> ../markdown.cc:28:5: error: 'lowdown_opts' has no non-static data member named 'cols'
nix-cmd>    28 |     };
nix-cmd>       |     ^

The change adds version-based conditional to support both pre-1.4 and 1.4 forms of the initialization.

Closes: #12113

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[darix]

couldnt you just do something like

if lowdown.get_version.version_compare(">= 1.4")
   configdata.set('HAVE_LOWDOWN_1_4', lowdown.found().to_int())
endif

that would save you the 2nd finder?

https://mesonbuild.com/Syntax.html#if-statements
https://github.com/mesonbuild/meson/blob/master/mesonbuild/dependencies/base.py#L202

also will this be backported to the 2.24 branch?

[darix]

also shouldnt the patch also fix the autoconf based build system?

[darix]

Tested version (2.24.11)

diff --git a/src/libcmd/meson.build b/src/libcmd/meson.build
index c484cf998..2ae51a669 100644
--- a/src/libcmd/meson.build
+++ b/src/libcmd/meson.build
@@ -38,6 +38,10 @@ deps_public += nlohmann_json
 lowdown = dependency('lowdown', version : '>= 0.9.0', required : get_option('markdown'))
 deps_private += lowdown
 configdata.set('HAVE_LOWDOWN', lowdown.found().to_int())
+# The API changed slightly around terminal initialization.
+if lowdown.version().version_compare('>= 1.4')
+  configdata.set('HAVE_LOWDOWN_1_4', lowdown.found().to_int())
+endif
 
 readline_flavor = get_option('readline-flavor')
 if readline_flavor == 'editline'

[trofi]

couldnt you just do something like

if lowdown.get_version.version_compare(">= 1.4")
   configdata.set('HAVE_LOWDOWN_1_4', lowdown.found().to_int())
endif

Sounds reasonable. I would prefer to set the value unconditionally to allow integer context in #if FOO to catch typos (as opposed to #ifdef FOO). Updated the patch to:

--- a/src/libcmd/meson.build
+++ b/src/libcmd/meson.build
@@ -38,2 +38,4 @@ deps_private += lowdown
 configdata.set('HAVE_LOWDOWN', lowdown.found().to_int())
+# The API changed slightly around terminal initialization.
+configdata.set('HAVE_LOWDOWN_1_4', lowdown.version().version_compare('>= 1.4.0').to_int())

also will this be backported to the 2.24 branch?

Probably not as is as autotools build system was removed from master.

[roberth]

A backport to 2.24 would have to include autotools support, or you'd still be stuck on lowdown 1.3 only.
I'll trigger the automation anyway, if that's helpful.

[darix]

well yeah i tried to use meson with 2.24 in my package but that version of the meson build was quite incomplete compared to autotools and 2.25 still waits for libgit2 to be merged :)