pkg/fontconfig: pattern get

pkg/fontconfig/common.zig

@@ -1,5 +1,6 @@
 const std = @import("std");
 const c = @import("c.zig");
+const Error = @import("main.zig").Error;
 
 pub const Weight = enum(c_uint) {
     thin = c.FC_WEIGHT_THIN,
@@ -111,6 +112,16 @@ pub const Result = enum(c_uint) {
     type_mismatch = c.FcResultTypeMismatch,
     no_id = c.FcResultNoId,
     out_of_memory = c.FcResultOutOfMemory,
+
+    pub fn toError(self: Result) Error!void {
+        return switch (self) {
+            .match => {},
+            .no_match => Error.FontconfigNoMatch,
+            .type_mismatch => Error.FontconfigTypeMismatch,
+            .no_id => Error.FontconfigNoId,
+            .out_of_memory => Error.OutOfMemory,
+        };
+    }
 };
 
 pub const MatchKind = enum(c_uint) {

pkg/fontconfig/error.zig

@@ -1,3 +1,7 @@
 pub const Error = error{
+    OutOfMemory,
     FontconfigFailed,
+    FontconfigNoMatch,
+    FontconfigTypeMismatch,
+    FontconfigNoId,
 };

pkg/fontconfig/pattern.zig

@@ -1,6 +1,7 @@
 const std = @import("std");
 const assert = std.debug.assert;
 const c = @import("c.zig");
+const Error = @import("main.zig").Error;
 const ObjectSet = @import("main.zig").ObjectSet;
 const Property = @import("main.zig").Property;
 const Result = @import("main.zig").Result;
@@ -34,6 +35,18 @@ pub const Pattern = opaque {
         ) == c.FcTrue;
     }
 
+    pub fn get(self: *Pattern, prop: Property, id: u32) Error!Value {
+        var val: c.struct__FcValue = undefined;
+        try @intToEnum(Result, c.FcPatternGet(
+            self.cval(),
+            prop.cval(),
+            @intCast(c_int, id),
+            &val,
+        )).toError();
+
+        return Value.init(&val);
+    }
+
     pub fn delete(self: *Pattern, prop: Property) bool {
         return c.FcPatternDel(self.cval(), prop.cval()) == c.FcTrue;
     }
@@ -142,6 +155,12 @@ test "create" {
 
     try testing.expect(pat.add(.family, .{ .string = "monospace" }, false));
     try testing.expect(pat.add(.weight, .{ .integer = @enumToInt(Weight.bold) }, false));
+
+    {
+        const val = try pat.get(.family, 0);
+        try testing.expect(val == .string);
+        try testing.expectEqualStrings("monospace", val.string);
+    }
 }
 
 test "name parse" {