Support global flags after specs

Author: benjyw

src/rust/pants_ng/options/src/pants_invocation.rs

@@ -166,7 +166,7 @@ impl PantsInvocation {
 
         let mut unconsumed_args = args.arg_strings.into_iter().peekable();
 
-        let global_flags = consume_flags(&mut unconsumed_args);
+        let mut global_flags = consume_flags(&mut unconsumed_args);
 
         let mut commands = vec![];
         let mut cmd_opt = consume_cmd(&mut unconsumed_args);
@@ -191,6 +191,10 @@ impl PantsInvocation {
             ));
         }
 
+        // Any flags after specs (but before passthru args) are considered to be global flags.
+        // This makes it convenient to tack flags on at the end of an existing cmd line.
+        global_flags.append(&mut consume_flags(&mut unconsumed_args));
+
         let mut passthru = None;
         if let Some(s) = unconsumed_args.next() {
             if s == "--" {

src/rust/pants_ng/options/src/pants_invocation_tests.rs

@@ -277,9 +277,23 @@ fn test_command_and_subcommand() {
     );
 
     assert_eq!(
-        mk_invocation("pants --foo cmd --bar=baz subcmd --qux=quux path/to/file1 ./path2 -- passthru_arg --passthru-flag").unwrap(),
+        mk_invocation("pants --foo cmd --bar=baz subcmd --qux=quux path/to/file1 ./path2 --global-flag-after-specs=val").unwrap(),
         PantsInvocation {
-            global_flags: vec![mk_flag("foo", None),],
+            global_flags: vec![mk_flag("foo", None), mk_flag("global-flag-after-specs", Some("val")),],
+            commands: vec![mk_command(
+                "cmd",
+                vec![mk_flag("bar", Some("baz")),],
+                Some(mk_subcommand("subcmd", vec![mk_flag("qux", Some("quux"))]))
+            )],
+            specs: vec!["path/to/file1".to_string(), "./path2".to_string()],
+            passthru: None,
+        },
+    );
+
+    assert_eq!(
+        mk_invocation("pants --foo cmd --bar=baz subcmd --qux=quux path/to/file1 ./path2 --global-flag-after-specs -- passthru_arg --passthru-flag").unwrap(),
+        PantsInvocation {
+            global_flags: vec![mk_flag("foo", None), mk_flag("global-flag-after-specs", None),],
             commands: vec![mk_command(
                 "cmd",
                 vec![mk_flag("bar", Some("baz")),],
@@ -311,9 +325,9 @@ fn test_multiple_commands_and_subcommands() {
     );
 
     assert_eq!(
-        mk_invocation("pants --global-flag cmd1 --cmd1-flag subcmd1 --subcmd1-flag + cmd2 --cmd2-flag + cmd3 --cmd3-flag subcmd3 --subcmd3-flag path/to/spec -- passthru").unwrap(),
+        mk_invocation("pants --global-flag cmd1 --cmd1-flag subcmd1 --subcmd1-flag + cmd2 --cmd2-flag + cmd3 --cmd3-flag subcmd3 --subcmd3-flag path/to/spec --another-global-flag -- passthru").unwrap(),
         PantsInvocation {
-            global_flags: vec![mk_flag("global-flag", None)],
+            global_flags: vec![mk_flag("global-flag", None), mk_flag("another-global-flag", None),],
             commands: vec![mk_command(
                 "cmd1",
                 vec![mk_flag("cmd1-flag", None)],