add usergids

src/compress.zig

@@ -5,6 +5,9 @@
 // golang's varint implementation.
 const std = @import("std");
 
+const ArrayList = std.ArrayList;
+const Allocator = std.mem.Allocator;
+
 // compresses a strictly incrementing sorted slice of integers using delta
 // compression. Compression is in-place.
 pub fn deltaCompress(comptime T: type, elems: []T) error{NotSorted}!void {
@@ -48,7 +51,7 @@ test "delta compress/decompress" {
         .{ .input = &[_]u8{ 0, 254, 255 }, .want = &[_]u8{ 0, 253, 0 } },
     };
     for (tests) |t| {
-        var arr = try std.ArrayList(u8).initCapacity(
+        var arr = try ArrayList(u8).initCapacity(
             testing.allocator,
             t.input.len,
         );
@@ -69,7 +72,7 @@ test "delta compression negative tests" {
         &[_]u8{ 0, 1, 1 },
         &[_]u8{ 0, 1, 2, 1 },
     }) |t| {
-        var arr = try std.ArrayList(u8).initCapacity(testing.allocator, t.len);
+        var arr = try ArrayList(u8).initCapacity(testing.allocator, t.len);
         defer arr.deinit();
         try arr.appendSlice(t);
         try testing.expectError(error.NotSorted, deltaCompress(u8, arr.items));
@@ -81,7 +84,7 @@ test "delta decompress overflow" {
         &[_]u8{ 255, 0 },
         &[_]u8{ 0, 128, 127 },
     }) |t| {
-        var arr = try std.ArrayList(u8).initCapacity(testing.allocator, t.len);
+        var arr = try ArrayList(u8).initCapacity(testing.allocator, t.len);
         defer arr.deinit();
         try arr.appendSlice(t);
         try testing.expectError(error.Overflow, deltaDecompress(u8, arr.items));
@@ -142,24 +145,31 @@ pub fn putUvarint(buf: []u8, x: u64) usize {
     return i + 1;
 }
 
-test "uvarint" {
-    const uvarint_tests = [_]u64{
-        0,
-        1,
-        2,
-        10,
-        20,
-        63,
-        64,
-        65,
-        127,
-        128,
-        129,
-        255,
-        256,
-        257,
-        1 << 63 - 1,
-    };
+pub fn appendUvarint(arr: *ArrayList(u8), x: u64) Allocator.Error!void {
+    var buf: [maxVarintLen64]u8 = undefined;
+    const n = putUvarint(&buf, x);
+    try arr.appendSlice(buf[0..n]);
+}
+
+const uvarint_tests = [_]u64{
+    0,
+    1,
+    2,
+    10,
+    20,
+    63,
+    64,
+    65,
+    127,
+    128,
+    129,
+    255,
+    256,
+    257,
+    1 << 63 - 1,
+};
+
+test "putUvarint/uvarint" {
     for (uvarint_tests) |x| {
         var buf: [maxVarintLen64]u8 = undefined;
         const n = putUvarint(buf[0..], x);
@@ -170,6 +180,18 @@ test "uvarint" {
     }
 }
 
+test "appendUvarint" {
+    for (uvarint_tests) |x| {
+        var buf = ArrayList(u8).init(testing.allocator);
+        defer buf.deinit();
+
+        try appendUvarint(&buf, x);
+        const got = try uvarint(buf.items);
+
+        try testing.expectEqual(x, got.value);
+    }
+}
+
 test "overflow" {
     for ([_][]const u8{
         &[_]u8{ 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x2 },