This had two issues in the Meson build system: it was always set to true even if configured with -Dyaml=disabled, and the #ifdef FLATPAK_BUILDER_ENABLE_YAML check always succeeded because set10 defines the macro to 1 or 0. Use set with a boolean value instead, which defines or undefines the macro, leading to the same interface as in Autotools.
This is not hugely important, I don't know whether anyone actually disables YAML in practice - it's an extra dependency, but YAML is so much nicer as a human-written format than JSON.
The other possibility here would be to remove the option, and say that 1.3.x/1.4.x unconditionally supports YAML manifests.
This had two issues in the Meson build system: it was always set to true even if configured with
-Dyaml=disabled, and the#ifdef FLATPAK_BUILDER_ENABLE_YAMLcheck always succeeded becauseset10defines the macro to 1 or 0. Usesetwith a boolean value instead, which defines or undefines the macro, leading to the same interface as in Autotools.This is not hugely important, I don't know whether anyone actually disables YAML in practice - it's an extra dependency, but YAML is so much nicer as a human-written format than JSON.
The other possibility here would be to remove the option, and say that 1.3.x/1.4.x unconditionally supports YAML manifests.