Add script to generate markdown CI badges

scripts/generate_badges.d

@@ -0,0 +1,139 @@
+import std.algorithm : each, map, cartesianProduct, filter;
+import std.array : array;
+import std.conv : to;
+import std.format;
+import std.range : chain, only;
+import std.stdio;
+import std.traits : EnumMembers;
+
+enum Cpu
+{
+    amd64,
+    AArch64,
+    ARM,
+    MIPS
+}
+
+enum Os
+{
+    FreeBSD,
+    Linux,
+    MacOS,
+    Windows
+}
+
+string getWorkflowName(Cpu cpu)
+{
+    final switch (cpu)
+    {
+    case Cpu.amd64:
+        return "amd64";
+    case Cpu.AArch64:
+        return "aarch64";
+    case Cpu.ARM:
+        return "arm";
+    case Cpu.MIPS:
+        return "mips";
+    }
+}
+
+string getWorkflowName(Os os)
+{
+    final switch (os)
+    {
+    case Os.FreeBSD:
+        return "FreeBSD";
+    case Os.Linux:
+        return "Linux";
+    case Os.MacOS:
+        return "macOS";
+    case Os.Windows:
+        return "Windows";
+    }
+}
+
+struct Configuration
+{
+const:
+    Cpu cpu;
+    Os os;
+
+    bool disabled()
+    {
+        import std.algorithm.comparison : among;
+
+        return os.among(Os.FreeBSD, Os.Windows, Os.MacOS) && cpu.among(Cpu.AArch64, Cpu.ARM, Cpu
+                .MIPS);
+    }
+
+    string cell()
+    {
+        return format("%d%c", cast(uint)(os) + 1, cast(char)('a' + cpu));
+    }
+
+    string link_ref()
+    {
+        return format("[lnk_%s]", cell());
+    }
+
+    string image_ref()
+    {
+        return format("[img_%s]", cell());
+    }
+
+    string cell_text()
+    {
+        if (disabled())
+            return "![][img_na]";
+        return format("[![]%s]%s", image_ref, link_ref);
+    }
+
+}
+
+immutable allCpus = [EnumMembers!Cpu];
+immutable allOses = [EnumMembers!Os];
+
+auto tableHeader(in Cpu[] cpus)
+{
+    return chain(only("Os"), cpus.map!(to!string)).array;
+}
+
+auto tableAlignment(in Cpu[] cpus)
+{
+    return chain(only(":--"), cpus.map!(v => "--:")).array;
+}
+
+auto tableRow(in Os os, in Cpu[] cpus)
+{
+    return chain(only(os.to!string), cpus.map!(cpu => Configuration(cpu, os).cell_text())).array;
+}
+
+auto tableRows(in Os[] oses, in Cpu[] cpus)
+{
+    return oses.map!(os => tableRow(os, cpus)).array;
+}
+
+auto table(in Os[] oses, in Cpu[] cpus)
+{
+    return chain(only(tableHeader(cpus)), only(tableAlignment(cpus)), tableRows(oses, cpus));
+}
+
+void main()
+{
+    immutable allCpus = [EnumMembers!Cpu];
+    immutable allOses = [EnumMembers!Os];
+
+    writefln("%(|%-( %-21s |%) |\n%) |", table(allOses, allCpus));
+    writeln();
+    writeln("[img_na]: https://img.shields.io/badge/build-N%2FA-lightgrey");
+    cartesianProduct(allCpus, allOses)
+        .map!(t => Configuration(t[0], t[1]))
+        .filter!(conf => !conf.disabled)
+        .each!((conf) {
+            const cpu_name = getWorkflowName(conf.cpu);
+            const os_name = getWorkflowName(conf.os);
+            writefln("%s: https://github.com/google/cpu_features/actions/workflows/%s_%s.yml", conf.link_ref, cpu_name, os_name);
+            writefln("%s: https://img.shields.io/github/workflow/status/google/cpu_features/%s%%20%s/main", conf
+                .image_ref, cpu_name, os_name);
+        });
+}