diff --git a/src/command.rs b/src/command.rs
index 578677e..b433b0f 100644
--- a/src/command.rs
+++ b/src/command.rs
@@ -1,4 +1,4 @@
-use std::collections::{HashSet, VecDeque};
+use std::collections::{BTreeSet, HashSet, VecDeque};
 use std::error::Error;
 
 /// A block, consisting of multiple commands.
@@ -14,7 +14,7 @@ pub(crate) struct Block {
 }
 
 /// A command.
-#[derive(Clone, Debug, PartialEq)]
+#[derive(Clone, PartialEq)]
 #[non_exhaustive]
 pub struct Command {
     /// The name of the command. Never empty.
@@ -35,6 +35,21 @@ pub struct Command {
     pub line_number: u32,
 }
 
+impl std::fmt::Debug for Command {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("Command")
+            .field("name", &self.name)
+            .field("args", &self.args)
+            .field("prefix", &self.prefix)
+            // Use a sorted BTreeSet for test determinism.
+            .field("tags", &BTreeSet::from_iter(&self.tags))
+            .field("silent", &self.silent)
+            .field("fail", &self.fail)
+            .field("line_number", &self.line_number)
+            .finish()
+    }
+}
+
 impl Command {
     /// Returns an argument consumer, for more convenient argument processing.
     /// Does not affect [`Command::args`].
diff --git a/tests/generate/empty_output.out b/tests/generate/empty_output.out
index fd884d7..09688a6 100644
--- a/tests/generate/empty_output.out
+++ b/tests/generate/empty_output.out
@@ -2,12 +2,12 @@
 # an empty block at the end of the file.
 command
 ---
-Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 3 }
+Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 3 }
 
 command
 ---
-Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 6 }
+Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 6 }
 
 command
 ---
-Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 9 }
+Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 9 }
diff --git a/tests/scripts/commands b/tests/scripts/commands
index 62953fc..f8a8953 100644
--- a/tests/scripts/commands
+++ b/tests/scripts/commands
@@ -1,51 +1,51 @@
 # A bare command.
 command
 ---
-Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 2 }
+Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 2 }
 
 # Commands with arguments.
 foo arg
 bar key=value
 baz arg key=value
 ---
-Command { name: "foo", args: [Argument { key: None, value: "arg" }], prefix: None, tags: [], silent: false, fail: false, line_number: 7 }
-Command { name: "bar", args: [Argument { key: Some("key"), value: "value" }], prefix: None, tags: [], silent: false, fail: false, line_number: 8 }
-Command { name: "baz", args: [Argument { key: None, value: "arg" }, Argument { key: Some("key"), value: "value" }], prefix: None, tags: [], silent: false, fail: false, line_number: 9 }
+Command { name: "foo", args: [Argument { key: None, value: "arg" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 7 }
+Command { name: "bar", args: [Argument { key: Some("key"), value: "value" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 8 }
+Command { name: "baz", args: [Argument { key: None, value: "arg" }, Argument { key: Some("key"), value: "value" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 9 }
 
 # Commands with tags.
 foo [tag]
 foo arg key=value [a,b c]
 ---
-Command { name: "foo", args: [], prefix: None, tags: ["tag"], silent: false, fail: false, line_number: 16 }
-Command { name: "foo", args: [Argument { key: None, value: "arg" }, Argument { key: Some("key"), value: "value" }], prefix: None, tags: ["a", "b", "c"], silent: false, fail: false, line_number: 17 }
+Command { name: "foo", args: [], prefix: None, tags: {"tag"}, silent: false, fail: false, line_number: 16 }
+Command { name: "foo", args: [Argument { key: None, value: "arg" }, Argument { key: Some("key"), value: "value" }], prefix: None, tags: {"a", "b", "c"}, silent: false, fail: false, line_number: 17 }
 
 # Commands with prefixes.
 a: foo arg
 b: bar key=value
 ---
-a: Command { name: "foo", args: [Argument { key: None, value: "arg" }], prefix: Some("a"), tags: [], silent: false, fail: false, line_number: 23 }
-b: Command { name: "bar", args: [Argument { key: Some("key"), value: "value" }], prefix: Some("b"), tags: [], silent: false, fail: false, line_number: 24 }
+a: Command { name: "foo", args: [Argument { key: None, value: "arg" }], prefix: Some("a"), tags: {}, silent: false, fail: false, line_number: 23 }
+b: Command { name: "bar", args: [Argument { key: Some("key"), value: "value" }], prefix: Some("b"), tags: {}, silent: false, fail: false, line_number: 24 }
 
 # Failing commands.
 ! foo bar
 ---
-Error: Command { name: "foo", args: [Argument { key: None, value: "bar" }], prefix: None, tags: [], silent: false, fail: true, line_number: 30 }
+Error: Command { name: "foo", args: [Argument { key: None, value: "bar" }], prefix: None, tags: {}, silent: false, fail: true, line_number: 30 }
 
 # Prefixes, commands, and keys can be empty.
 "": "" ""=""
 ---
-: Command { name: "", args: [Argument { key: Some(""), value: "" }], prefix: Some(""), tags: [], silent: false, fail: false, line_number: 35 }
+: Command { name: "", args: [Argument { key: Some(""), value: "" }], prefix: Some(""), tags: {}, silent: false, fail: false, line_number: 35 }
 
 # Prefixes, commands, and keys can be whitespace.
 " ": " " " "=" "
 ---
- : Command { name: " ", args: [Argument { key: Some(" "), value: " " }], prefix: Some(" "), tags: [], silent: false, fail: false, line_number: 40 }
+ : Command { name: " ", args: [Argument { key: Some(" "), value: " " }], prefix: Some(" "), tags: {}, silent: false, fail: false, line_number: 40 }
 
 # Empty argument keys and values are fine.
 command ""
 command arg=""
 command arg=
 ---
-Command { name: "command", args: [Argument { key: None, value: "" }], prefix: None, tags: [], silent: false, fail: false, line_number: 45 }
-Command { name: "command", args: [Argument { key: Some("arg"), value: "" }], prefix: None, tags: [], silent: false, fail: false, line_number: 46 }
-Command { name: "command", args: [Argument { key: Some("arg"), value: "" }], prefix: None, tags: [], silent: false, fail: false, line_number: 47 }
+Command { name: "command", args: [Argument { key: None, value: "" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 45 }
+Command { name: "command", args: [Argument { key: Some("arg"), value: "" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 46 }
+Command { name: "command", args: [Argument { key: Some("arg"), value: "" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 47 }
diff --git a/tests/scripts/comments b/tests/scripts/comments
index af664a9..3d7eeb3 100644
--- a/tests/scripts/comments
+++ b/tests/scripts/comments
@@ -5,25 +5,25 @@
 # Comment before command.
 command id=1
 ---
-Command { name: "command", args: [Argument { key: Some("id"), value: "1" }], prefix: None, tags: [], silent: false, fail: false, line_number: 6 }
+Command { name: "command", args: [Argument { key: Some("id"), value: "1" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 6 }
 
 command id=2 # Comment beside command.
 ---
-Command { name: "command", args: [Argument { key: Some("id"), value: "2" }], prefix: None, tags: [], silent: false, fail: false, line_number: 10 }
+Command { name: "command", args: [Argument { key: Some("id"), value: "2" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 10 }
 
 command id=3
 # Comment after command.
 ---
-Command { name: "command", args: [Argument { key: Some("id"), value: "3" }], prefix: None, tags: [], silent: false, fail: false, line_number: 14 }
+Command { name: "command", args: [Argument { key: Some("id"), value: "3" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 14 }
 
 # Comment between blocks.
 
 command id=4
 ---
-Command { name: "command", args: [Argument { key: Some("id"), value: "4" }], prefix: None, tags: [], silent: false, fail: false, line_number: 21 }
+Command { name: "command", args: [Argument { key: Some("id"), value: "4" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 21 }
 
 command id=5 // Comment using //.
 ---
-Command { name: "command", args: [Argument { key: Some("id"), value: "5" }], prefix: None, tags: [], silent: false, fail: false, line_number: 25 }
+Command { name: "command", args: [Argument { key: Some("id"), value: "5" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 25 }
 
 # Comment at end.
\ No newline at end of file
diff --git a/tests/scripts/dos_line_endings b/tests/scripts/dos_line_endings
index b61cebc..19ff71b 100644
--- a/tests/scripts/dos_line_endings
+++ b/tests/scripts/dos_line_endings
@@ -2,7 +2,7 @@
 
 command
 ---
-Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 3 }
+Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 3 }
 
 // Comment.
 
@@ -10,9 +10,9 @@ foo arg
 bar key=value
 baz arg key=value
 ---
-Command { name: "foo", args: [Argument { key: None, value: "arg" }], prefix: None, tags: [], silent: false, fail: false, line_number: 9 }
-Command { name: "bar", args: [Argument { key: Some("key"), value: "value" }], prefix: None, tags: [], silent: false, fail: false, line_number: 10 }
-Command { name: "baz", args: [Argument { key: None, value: "arg" }, Argument { key: Some("key"), value: "value" }], prefix: None, tags: [], silent: false, fail: false, line_number: 11 }
+Command { name: "foo", args: [Argument { key: None, value: "arg" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 9 }
+Command { name: "bar", args: [Argument { key: Some("key"), value: "value" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 10 }
+Command { name: "baz", args: [Argument { key: None, value: "arg" }, Argument { key: Some("key"), value: "value" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 11 }
 
 # Comment.
 a: foo arg
@@ -20,7 +20,7 @@ a: foo arg
 b: bar key=value
 # Comment.
 ---
-a: Command { name: "foo", args: [Argument { key: None, value: "arg" }], prefix: Some("a"), tags: [], silent: false, fail: false, line_number: 18 }
-b: Command { name: "bar", args: [Argument { key: Some("key"), value: "value" }], prefix: Some("b"), tags: [], silent: false, fail: false, line_number: 20 }
+a: Command { name: "foo", args: [Argument { key: None, value: "arg" }], prefix: Some("a"), tags: {}, silent: false, fail: false, line_number: 18 }
+b: Command { name: "bar", args: [Argument { key: Some("key"), value: "value" }], prefix: Some("b"), tags: {}, silent: false, fail: false, line_number: 20 }
 
 # Comment.
\ No newline at end of file
diff --git a/tests/scripts/fail b/tests/scripts/fail
index e834dfb..dedc28a 100644
--- a/tests/scripts/fail
+++ b/tests/scripts/fail
@@ -2,7 +2,7 @@
 # the runner expects an error.
 ! command arg
 ---
-Error: Command { name: "command", args: [Argument { key: None, value: "arg" }], prefix: None, tags: [], silent: false, fail: true, line_number: 3 }
+Error: Command { name: "command", args: [Argument { key: None, value: "arg" }], prefix: None, tags: {}, silent: false, fail: true, line_number: 3 }
 
 # Errors and panics are handled when ! is given.
 ! _error foo
diff --git a/tests/scripts/hooks b/tests/scripts/hooks
index 2ae4815..e1335fd 100644
--- a/tests/scripts/hooks
+++ b/tests/scripts/hooks
@@ -2,13 +2,13 @@
 _set start_block="start" end_block="end"
 command
 ---
-Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 3 }
+Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 3 }
 end
 
 command
 ---
 start
-Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 8 }
+Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 8 }
 end
 
 # Newlines in block hooks should be handled appropriately.
@@ -16,13 +16,13 @@ _set start_block="start\n" end_block="end\n"
 command
 ---
 start
-Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 16 }
+Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 16 }
 end
 
 command
 ---
 start
-Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 22 }
+Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 22 }
 end
 
 # As should empty lines.
@@ -30,7 +30,7 @@ _set start_block="start\n\n" end_block="end\n\n"
 command
 ---
 > start
-> Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 30 }
+> Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 30 }
 > end
 > 
 
@@ -39,7 +39,7 @@ command
 ---
 > start
 > 
-> Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 38 }
+> Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 38 }
 > end
 
 _set start_block="" end_block=""
@@ -55,10 +55,10 @@ prefix: command
 (command)
 ---
 start
-Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 53 }
+Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 53 }
 end
 prefix: start
-prefix: Command { name: "command", args: [], prefix: Some("prefix"), tags: [], silent: false, fail: false, line_number: 54 }
+prefix: Command { name: "command", args: [], prefix: Some("prefix"), tags: {}, silent: false, fail: false, line_number: 54 }
 prefix: end
 
 # They should also be called after commands that were expected to fail.
@@ -73,7 +73,7 @@ end
 command
 ---
 start
-Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 73 }
+Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 73 }
 end
 
 (_set start_command="start\n\n" end_command="end\n\n")
@@ -81,6 +81,6 @@ command
 ---
 > start
 > 
-> Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 80 }
+> Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 80 }
 > end
 > 
diff --git a/tests/scripts/output b/tests/scripts/output
index f97b597..b3981d4 100644
--- a/tests/scripts/output
+++ b/tests/scripts/output
@@ -2,8 +2,8 @@
 command
 command arg
 ---
-Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 2 }
-Command { name: "command", args: [Argument { key: None, value: "arg" }], prefix: None, tags: [], silent: false, fail: false, line_number: 3 }
+Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 2 }
+Command { name: "command", args: [Argument { key: None, value: "arg" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 3 }
 
 # Output that contains empty lines should automatically be prefixed with >.
 # This should be the case for empty lines at the start and end of the output,
@@ -13,17 +13,17 @@ command id=1
 command id=2
 ---
 > 
-> Command { name: "command", args: [Argument { key: Some("id"), value: "1" }], prefix: None, tags: [], silent: false, fail: false, line_number: 12 }
+> Command { name: "command", args: [Argument { key: Some("id"), value: "1" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 12 }
 > 
-> Command { name: "command", args: [Argument { key: Some("id"), value: "2" }], prefix: None, tags: [], silent: false, fail: false, line_number: 13 }
+> Command { name: "command", args: [Argument { key: Some("id"), value: "2" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 13 }
 
 _set prefix="" suffix="\n\n"
 command id=1
 command id=2
 ---
-> Command { name: "command", args: [Argument { key: Some("id"), value: "1" }], prefix: None, tags: [], silent: false, fail: false, line_number: 21 }
+> Command { name: "command", args: [Argument { key: Some("id"), value: "1" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 21 }
 > 
-> Command { name: "command", args: [Argument { key: Some("id"), value: "2" }], prefix: None, tags: [], silent: false, fail: false, line_number: 22 }
+> Command { name: "command", args: [Argument { key: Some("id"), value: "2" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 22 }
 > 
 
 _set prefix="\n" suffix="\n\n"
@@ -31,10 +31,10 @@ command id=1
 command id=2
 ---
 > 
-> Command { name: "command", args: [Argument { key: Some("id"), value: "1" }], prefix: None, tags: [], silent: false, fail: false, line_number: 30 }
+> Command { name: "command", args: [Argument { key: Some("id"), value: "1" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 30 }
 > 
 > 
-> Command { name: "command", args: [Argument { key: Some("id"), value: "2" }], prefix: None, tags: [], silent: false, fail: false, line_number: 31 }
+> Command { name: "command", args: [Argument { key: Some("id"), value: "2" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 31 }
 > 
 
 # Empty output blocks should default to "ok", but only once, and only if none of
@@ -54,7 +54,7 @@ ok
 command
 (command)
 ---
-Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 54 }
+Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 54 }
 
 _set start_block="" end_block="end"
 ---
diff --git a/tests/scripts/silent b/tests/scripts/silent
index 06cad9b..259ef0b 100644
--- a/tests/scripts/silent
+++ b/tests/scripts/silent
@@ -8,8 +8,8 @@ command id=1
 (command id=2)
 command id=3
 ---
-Command { name: "command", args: [Argument { key: Some("id"), value: "1" }], prefix: None, tags: [], silent: false, fail: false, line_number: 7 }
-Command { name: "command", args: [Argument { key: Some("id"), value: "3" }], prefix: None, tags: [], silent: false, fail: false, line_number: 9 }
+Command { name: "command", args: [Argument { key: Some("id"), value: "1" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 7 }
+Command { name: "command", args: [Argument { key: Some("id"), value: "3" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 9 }
 
 # Whitespace is allowed around the parentheses, except for the first.
 ( command  )  # eol
diff --git a/tests/scripts/strings b/tests/scripts/strings
index 0a7d3fd..4833ba5 100644
--- a/tests/scripts/strings
+++ b/tests/scripts/strings
@@ -2,18 +2,18 @@
 0: 1 2 3=4
 01: 23 45 67=89
 ---
-0: Command { name: "1", args: [Argument { key: None, value: "2" }, Argument { key: Some("3"), value: "4" }], prefix: Some("0"), tags: [], silent: false, fail: false, line_number: 2 }
-01: Command { name: "23", args: [Argument { key: None, value: "45" }, Argument { key: Some("67"), value: "89" }], prefix: Some("01"), tags: [], silent: false, fail: false, line_number: 3 }
+0: Command { name: "1", args: [Argument { key: None, value: "2" }, Argument { key: Some("3"), value: "4" }], prefix: Some("0"), tags: {}, silent: false, fail: false, line_number: 2 }
+01: Command { name: "23", args: [Argument { key: None, value: "45" }, Argument { key: Some("67"), value: "89" }], prefix: Some("01"), tags: {}, silent: false, fail: false, line_number: 3 }
 
 # Unquoted strings can start with _.
 _prefix: _command _arg _key=_value
 ---
-_prefix: Command { name: "_command", args: [Argument { key: None, value: "_arg" }, Argument { key: Some("_key"), value: "_value" }], prefix: Some("_prefix"), tags: [], silent: false, fail: false, line_number: 9 }
+_prefix: Command { name: "_command", args: [Argument { key: None, value: "_arg" }, Argument { key: Some("_key"), value: "_value" }], prefix: Some("_prefix"), tags: {}, silent: false, fail: false, line_number: 9 }
 
 # Unquoted strings can contain -_./@
 prefix-_.: command-_./@ arg-_./@ key-_./@=value-_./@
 ---
-prefix-_.: Command { name: "command-_./@", args: [Argument { key: None, value: "arg-_./@" }, Argument { key: Some("key-_./@"), value: "value-_./@" }], prefix: Some("prefix-_."), tags: [], silent: false, fail: false, line_number: 14 }
+prefix-_.: Command { name: "command-_./@", args: [Argument { key: None, value: "arg-_./@" }, Argument { key: Some("key-_./@"), value: "value-_./@" }], prefix: Some("prefix-_."), tags: {}, silent: false, fail: false, line_number: 14 }
 
 # Single-quoted strings can contain any character, including newlines.
 '➡️': '😀' '"👋"' '\t'='\0' '
@@ -22,7 +22,7 @@ prefix-_.: Command { name: "command-_./@", args: [Argument { key: None, value: "
 
 '
 ---
-➡️: Command { name: "😀", args: [Argument { key: None, value: "\"👋\"" }, Argument { key: Some("\t"), value: "\0" }, Argument { key: None, value: "\n\n  🚀\n\n" }], prefix: Some("➡\u{fe0f}"), tags: [], silent: false, fail: false, line_number: 19 }
+➡️: Command { name: "😀", args: [Argument { key: None, value: "\"👋\"" }, Argument { key: Some("\t"), value: "\0" }, Argument { key: None, value: "\n\n  🚀\n\n" }], prefix: Some("➡\u{fe0f}"), tags: {}, silent: false, fail: false, line_number: 19 }
 
 # Double-quoted strings can too.
 "➡️": "😀" "'👋'" "\t"="\0" "
@@ -31,37 +31,37 @@ prefix-_.: Command { name: "command-_./@", args: [Argument { key: None, value: "
 
 "
 ---
-➡️: Command { name: "😀", args: [Argument { key: None, value: "'👋'" }, Argument { key: Some("\t"), value: "\0" }, Argument { key: None, value: "\n\n  🚀\n\n" }], prefix: Some("➡\u{fe0f}"), tags: [], silent: false, fail: false, line_number: 28 }
+➡️: Command { name: "😀", args: [Argument { key: None, value: "'👋'" }, Argument { key: Some("\t"), value: "\0" }, Argument { key: None, value: "\n\n  🚀\n\n" }], prefix: Some("➡\u{fe0f}"), tags: {}, silent: false, fail: false, line_number: 28 }
 
 # Single- and double-quoted strings can also be empty, but is not allowed in
 # identifiers (prefixes, commands, and argument names). It is allowed as
 # argument values.
 command foo="" bar=''
 ---
-Command { name: "command", args: [Argument { key: Some("foo"), value: "" }, Argument { key: Some("bar"), value: "" }], prefix: None, tags: [], silent: false, fail: false, line_number: 39 }
+Command { name: "command", args: [Argument { key: Some("foo"), value: "" }, Argument { key: Some("bar"), value: "" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 39 }
 
 # Escape sequences are respected both in single and double quotes, including
 # both quote types.
 '\\ \' \" \0 \n \r \t \\ \x00 \x7A \xff \u{1F44b}'
 "\\ \' \" \0 \n \r \t \\ \x00 \x7A \xff \u{1F44b}"
 ---
-Command { name: "\\ ' \" \0 \n \r \t \\ \0 z ÿ 👋", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 45 }
-Command { name: "\\ ' \" \0 \n \r \t \\ \0 z ÿ 👋", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 46 }
+Command { name: "\\ ' \" \0 \n \r \t \\ \0 z ÿ 👋", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 45 }
+Command { name: "\\ ' \" \0 \n \r \t \\ \0 z ÿ 👋", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 46 }
 
 # Quoted strings can contain the other, unescaped quote kind.
 '"'
 "'"
 ---
-Command { name: "\"", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 52 }
-Command { name: "'", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 53 }
+Command { name: "\"", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 52 }
+Command { name: "'", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 53 }
 
 # Quoted strings can also contain special characters like silencing ( and prefix
 # : without them being interpreted as such.
 '(command:' arg
 ---
-Command { name: "(command:", args: [Argument { key: None, value: "arg" }], prefix: None, tags: [], silent: false, fail: false, line_number: 60 }
+Command { name: "(command:", args: [Argument { key: None, value: "arg" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 60 }
 
 # They can also contain comments.
 'command # with comment'
 ---
-Command { name: "command # with comment", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 65 }
+Command { name: "command # with comment", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 65 }
diff --git a/tests/scripts/whitespace b/tests/scripts/whitespace
index 05d67e9..68048b3 100644
--- a/tests/scripts/whitespace
+++ b/tests/scripts/whitespace
@@ -8,7 +8,7 @@
 
 command
 ---
-Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail: false, line_number: 9 }
+Command { name: "command", args: [], prefix: None, tags: {}, silent: false, fail: false, line_number: 9 }
 
 
   # Comment.
@@ -18,7 +18,7 @@ Command { name: "command", args: [], prefix: None, tags: [], silent: false, fail
 
 command     arg
 ---
-Command { name: "command", args: [Argument { key: None, value: "arg" }], prefix: None, tags: [], silent: false, fail: false, line_number: 19 }
+Command { name: "command", args: [Argument { key: None, value: "arg" }], prefix: None, tags: {}, silent: false, fail: false, line_number: 19 }