wip: full smoke test

src/Group.zig

@@ -96,6 +96,19 @@ pub fn fromReader(allocator: Allocator, reader: anytype) FromReaderError![]Group
     return groups.toOwnedSlice();
 }
 
+pub fn writeTo(self: *const Group, writer: anytype) os.WriteError!void {
+    try writer.print("{s}:x:{d}:", .{ self.name, self.gid });
+    if (self.members.len == 0)
+        return;
+
+    try writer.writeAll(self.members[0]);
+
+    for (self.members[1..]) |member|
+        try writer.print(",{s}", .{member});
+
+    try writer.writeByte('\n');
+}
+
 // suggested buffer size in bytes if all strings were zero-terminated
 // (for CGroup).
 pub fn strlenZ(self: *const Group) usize {

src/User.zig

@@ -94,16 +94,17 @@ const max_line_len = fmt.count(line_fmt, .{
     max_user.shell,
 });
 
-// toPasswdLine formats the user in /etc/passwd format, including the EOL
-fn toLine(self: *const User) BoundedArray(u8, max_line_len) {
-    var result = BoundedArray(u8, max_line_len);
-    fmt.bufPrint(result.slice(), line_fmt, .{
+// toLine formats the user in /etc/passwd format, including the EOL
+pub fn toLine(self: *const User) BoundedArray(u8, max_line_len) {
+    var result = BoundedArray(u8, max_line_len).init(max_line_len) catch unreachable;
+    _ = fmt.bufPrint(result.slice(), line_fmt, .{
+        self.name,
         self.uid,
         self.gid,
         self.gecos,
         self.home,
         self.shell,
-    });
+    }) catch unreachable;
     return result;
 }
 

src/unix2db/main.zig

@@ -65,6 +65,7 @@ fn execute(
     const groupFname = result.argFlag("--group") orelse "./group";
     const outFile = result.argFlag("--output") orelse "./db.turbo";
 
+    std.debug.print("passwd file name: {s}\n", .{passwdFname});
     var passwdFile = try fs.cwd().openFile(passwdFname, .{ .mode = .read_only });
     defer passwdFile.close();
     var groupFile = try fs.cwd().openFile(groupFname, .{ .mode = .read_only });
@@ -80,7 +81,7 @@ fn execute(
     var db = try DB.fromCorpus(allocator, &corpus);
     defer db.deinit(allocator);
 
-    const fd = try os.open(outFile, os.O.WRONLY | os.O.TRUNC, 0644);
+    const fd = try os.open(outFile, os.O.WRONLY | os.O.TRUNC | os.O.CREAT, 0644);
     errdefer os.close(fd);
 
     const len = try os.writev(fd, db.iov().constSlice());
@@ -114,8 +115,57 @@ test "invalid argument" {
 
 test "smoke test" {
     const allocator = testing.allocator;
-    const args = &[_][*:0]const u8{"--invalid-argument"};
     var stderr = ArrayList(u8).init(allocator);
     defer stderr.deinit();
-    _ = args;
+
+    var corpus = try Corpus.testCorpus(allocator);
+    defer corpus.deinit();
+
+    var tmp = testing.tmpDir(.{});
+    //errdefer tmp.cleanup();
+
+    const tmp_path = blk: {
+        const relative_path = try fs.path.join(allocator, &[_][]const u8{
+            "zig-cache",
+            "tmp",
+            tmp.sub_path[0..],
+        });
+        const real_path = try fs.realpathAlloc(allocator, relative_path);
+        allocator.free(relative_path);
+        break :blk real_path;
+    };
+    defer allocator.free(tmp_path);
+
+    const passwdPath = try fs.path.joinZ(allocator, &[_][]const u8{ tmp_path, "passwd" });
+    defer allocator.free(passwdPath);
+    const groupPath = try fs.path.joinZ(allocator, &[_][]const u8{ tmp_path, "group" });
+    defer allocator.free(groupPath);
+    const outPath = try fs.path.joinZ(allocator, &[_][]const u8{ tmp_path, "tmp.turbo" });
+    defer allocator.free(outPath);
+
+    const passwd_fd = try os.open(passwdPath, os.O.CREAT | os.O.WRONLY, 0o644);
+    const group_fd = try os.open(groupPath, os.O.CREAT | os.O.WRONLY, 0o644);
+
+    var i: usize = 0;
+    while (i < corpus.users.len) : (i += 1) {
+        const user = corpus.users.get(i);
+        const line = user.toLine();
+        _ = try os.write(passwd_fd, line.constSlice());
+    }
+    os.close(passwd_fd);
+
+    var group_writer = (fs.File{ .handle = group_fd }).writer();
+    i = 0;
+    while (i < corpus.groups.len) : (i += 1)
+        try corpus.groups.get(i).writeTo(group_writer);
+    os.close(group_fd);
+
+    const args = &[_][*:0]const u8{
+        "--passwd", passwdPath,
+        "--group",  groupPath,
+        "--output", outPath,
+    };
+    const exit_code = try execute(allocator, stderr.writer(), args);
+
+    try testing.expectEqual(@as(u8, 0), exit_code);
 }