Provide formattable LogFormat object for VersionChecked

- Avoid internalising the logging function and instead expose a `std.fmt` api.

src/apprt/gtk/adw_version.zig

@@ -27,13 +27,16 @@ pub fn getRuntimeVersion() std.SemanticVersion {
     };
 }
 
-const AdwaitaVersion = VersionChecked("libadwaita", std.log.scoped(.gtk), getRuntimeVersion, comptime_version);
+const AdwaitaVersion = VersionChecked("libadwaita", getRuntimeVersion, comptime_version);
 
 pub const atLeast = AdwaitaVersion.atLeast;
 pub const until = AdwaitaVersion.until;
 pub const runtimeAtLeast = AdwaitaVersion.runtimeAtLeast;
 pub const runtimeUntil = AdwaitaVersion.runtimeUntil;
-pub const logVersion = AdwaitaVersion.logVersion;
+
+pub fn logVersion() void {
+    log.info("{s}", .{AdwaitaVersion.logFormat()});
+}
 
 // Whether AdwDialog, AdwAlertDialog, etc. are supported (1.5+)
 pub inline fn supportsDialogs() bool {

src/apprt/gtk/gtk_layer_version.zig

@@ -1,10 +1,16 @@
 const std = @import("std");
 const gtk4_layer_shell = @import("gtk4-layer-shell");
 const VersionChecked = @import("version.zig").VersionChecked;
+const log = std.log.scoped(.gtk);
 
 pub const getRuntimeVersion = gtk4_layer_shell.getRuntimeVersion;
-const LayerShellVersion = VersionChecked("gtk4-layer-shell", std.log.scoped(.gtk), getRuntimeVersion, null);
+const LayerShellVersion = VersionChecked("gtk4-layer-shell", getRuntimeVersion, null);
 
 pub const atLeast = LayerShellVersion.atLeast;
+pub const until = LayerShellVersion.until;
 pub const runtimeAtLeast = LayerShellVersion.runtimeAtLeast;
-pub const logVersion = LayerShellVersion.logVersion;
+pub const runtimeUntil = LayerShellVersion.until;
+
+pub fn logVersion() void {
+    log.info("{s}", .{LayerShellVersion.logFormat()});
+}

src/apprt/gtk/gtk_version.zig

@@ -9,6 +9,7 @@ const c = @cImport({
 
 const gtk = @import("gtk");
 const VersionChecked = @import("version.zig").VersionChecked;
+const log = std.log.scoped(.gtk);
 
 pub const comptime_version: std.SemanticVersion = .{
     .major = c.GTK_MAJOR_VERSION,
@@ -24,10 +25,13 @@ pub fn getRuntimeVersion() std.SemanticVersion {
     };
 }
 
-const GTKVersion = VersionChecked("GTK", std.log.scoped(.gtk), getRuntimeVersion, comptime_version);
+const GTKVersion = VersionChecked("GTK", getRuntimeVersion, comptime_version);
 
 pub const atLeast = GTKVersion.atLeast;
 pub const until = GTKVersion.until;
 pub const runtimeAtLeast = GTKVersion.runtimeAtLeast;
 pub const runtimeUntil = GTKVersion.runtimeUntil;
-pub const logVersion = GTKVersion.logVersion;
+
+pub fn logVersion() void {
+    log.info("{s}", .{GTKVersion.logFormat()});
+}

src/apprt/gtk/version.zig

@@ -1,20 +1,47 @@
 const std = @import("std");
 
-/// A generic way to dispatch version checks of a runtime dependency.
+/// A generic construct to dispatch version comparisons of a runtime dependency.
 ///
-/// The runtimeVersion function is expected to be created from the library we link against.
+/// The runtimeVersion function is to be created from the library we link against to detect a dynamically linked version.
 /// The comptime_version is optional
+///
+/// Whenever the runtimeVersion is required the provided function is called again, as opposed to being cached
 pub fn VersionChecked(
     comptime dependency_name: []const u8,
-    comptime log_scope: @TypeOf(std.log.scoped(.enum_literal)),
-    comptime getRuntimeVersion: fn () std.SemanticVersion,
+    comptime getRuntimeVersion_: fn () std.SemanticVersion,
     comptime comptime_version_: ?std.SemanticVersion,
 ) type {
     return struct {
         const Self = @This();
         const name = dependency_name;
-        const log = log_scope;
         const comptime_version = comptime_version_;
+        const getRuntimeVersion = getRuntimeVersion_;
+        pub const LogFormat = struct {
+            pub fn format(
+                _: LogFormat,
+                comptime _: []const u8,
+                _: std.fmt.FormatOptions,
+                writer: anytype,
+            ) !void {
+                if (Self.comptime_version) |comptime_version__| {
+                    try writer.print("{s} version build={} runtime={}", .{
+                        Self.name,
+                        comptime_version__,
+                        Self.getRuntimeVersion(),
+                    });
+                } else {
+                    try writer.print("{s} version runtime={}", .{
+                        Self.name,
+                        Self.getRuntimeVersion(),
+                    });
+                }
+            }
+        };
+
+        /// Provides an object that implements the std.fmt API intended for logging.
+        pub fn logFormat() LogFormat {
+            return .{};
+        }
 
         /// Verifies that the running dependency version is at least the given
         /// version.
@@ -84,7 +111,7 @@ pub fn VersionChecked(
         ) bool {
             // We use the functions instead of the constants such as c.GTK_MINOR_VERSION
             // because the function gets the actual runtime version.
-            const runtime_version = getRuntimeVersion();
+            const runtime_version = getRuntimeVersion_();
             return runtime_version.order(.{
                 .major = major,
                 .minor = minor,
@@ -103,7 +130,7 @@ pub fn VersionChecked(
             comptime minor: u16,
             comptime micro: u16,
         ) bool {
-            const runtime_version = getRuntimeVersion();
+            const runtime_version = getRuntimeVersion_();
             return runtime_version.order(.{
                 .major = major,
                 .minor = minor,
@@ -111,21 +138,6 @@ pub fn VersionChecked(
             }) == .lt;
         }
 
-        pub fn logVersion() void {
-            if (Self.comptime_version) |comptime_version__| {
-                Self.log.info("{s} version build={} runtime={}", .{
-                    Self.name,
-                    comptime_version__,
-                    getRuntimeVersion(),
-                });
-            } else {
-                Self.log.info("{s} version runtime={}", .{
-                    Self.name,
-                    getRuntimeVersion(),
-                });
-            }
-        }
-
         test "atLeast" {
             const testing = std.testing;
             const version = Self.comptime_version orelse std.SemanticVersion{ 1, 1, 1 };