Replace bespoke pwsh check with an integration test and trim comments

The vi edit-mode invariant now rides on the integration harness next to the
zsh regression test for the same defect (GH #7099), which exercises a real
Warpified session instead of a function lifted out of the bootstrap by AST
surgery. Drops script/test_pwsh_bootstrap and its CI and presubmit wiring.

Also cuts the rationale in pwsh.ps1 down to the part the code cannot say for
itself; the measurements and the prior-art history live on the PR and the
issue.

Author: warp-agent-staging[bot]

.github/workflows/ci.yml

@@ -681,10 +681,6 @@ jobs:
         run: ./script/lint_powershell -ci
         shell: pwsh
 
-      - name: Run pwsh bootstrap checks
-        run: ./script/test_pwsh_bootstrap -ci
-        shell: pwsh
-
       - name: Validate repo-sync markers
         uses: warpdotdev/repo-sync/actions/validate-markers@main
 

app/assets/bundled/bootstrap/pwsh.ps1

@@ -235,7 +235,6 @@ $null = New-Module -Name Warp-Module -ScriptBlock {
                 rcfiles_start_time = "$rcStartTime"
                 rcfiles_end_time = "$rcEndTime"
                 shell_plugins = ''
-                # The user's preference, not the session's live edit mode, which Warp overrides.
                 vi_mode_enabled = $(if ($script:viEditModeOverridden) { '1' } else { '' })
                 os_category = $osCategory
                 linux_distribution = "$linuxDistribution"
@@ -352,41 +351,19 @@ $null = New-Module -Name Warp-Module -ScriptBlock {
     # it is set to $false.
     $script:commandNotFound = $false
 
-    # Set when Warp turns off PSReadLine's vi edit mode for this session, so that the
-    # 'Bootstrapped' payload can still report the user's preference for vi keybindings.
-    # See Warp-Configure-PSReadLine for why the edit mode is overridden.
+    # Reports the user's vi preference in the 'Bootstrapped' payload even though the session's
+    # live edit mode is overridden. See Warp-Configure-PSReadLine.
     $script:viEditModeOverridden = $false
 
     function Warp-Configure-PSReadLine {
-        # Warp drives PSReadLine over the PTY with two chords that are a bare Escape plus a
-        # printable character: 'Alt+1' reports and drains the input buffer on every prompt, and
-        # 'Alt+2' clears it ahead of every submitted command. ConPTY readily delivers the two
-        # bytes in separate reads, and a chord split that way never dispatches, because 'Alt+1'
-        # is its own dispatch entry rather than the two-key chord 'Escape,1'. What the stray
-        # Escape then costs is entirely down to the edit mode. Measured on PSReadLine 2.3.5:
-        #
-        #   Emacs   Escape is bound to no function at all, only ever the first key of two-key
-        #           chords ('Escape,f' and friends), so the fragment resolves to an unbound chord
-        #           and is swallowed, leaving the buffer untouched.
-        #   Windows Escape is RevertLine, so the fragment clears the line and the digit then
-        #           self-inserts. That is the stray '1'/'2' prefix of GH #10891.
-        #   Vi      Escape is ViCommandMode, so the fragment strands the editor in command mode
-        #           and everything Warp writes next is reinterpreted as vi edits. A submitted
-        #           'echo hello' arrives as 'o hello'.
-        #
-        # Only vi is overridden, because only vi reinterprets the command. Windows edit mode is
-        # PSReadLine's default on Windows, so forcing Emacs there would reset the key handlers of
-        # every Windows user to address a milder, separately tracked defect. Nothing the user can
-        # see changes: their keystrokes go through Warp's own input editor, never PSReadLine's. A
-        # vi user does lose PSReadLine handlers registered elsewhere, since changing the edit mode
-        # resets them all; that is an accepted trade, because those handlers are equally
-        # unreachable inside Warp. fish resolves the same conflict the same way, resetting
-        # 'fish_key_bindings' to the defaults on every precmd.
-        #
-        # Reasserting this on every prompt, rather than once after the user's profile is sourced,
-        # also covers an edit mode set later in the session, from the next prompt onward. The
-        # check keeps that cheap and non-destructive, and the handler reset it guards against is
-        # why this has to precede the Set-PSReadLineKeyHandler calls below.
+        # The 'Alt+1' and 'Alt+2' chords below reach PSReadLine as a bare Escape plus a digit, and
+        # a chord split across reads -- which ConPTY readily produces -- never dispatches. Emacs
+        # swallows the stray Escape, but Vi binds it to ViCommandMode, so everything Warp writes
+        # next is reinterpreted as vi edits and 'echo hello' submits as 'o hello'. Only vi is
+        # overridden, because only vi corrupts the command; the milder stray-digit damage under
+        # the 'Windows' edit mode is GH #10891. The override costs a vi user nothing they can see,
+        # since a Warpified session's keystrokes go through Warp's input editor rather than
+        # PSReadLine's, and it must precede the bindings because it resets every key handler.
         if ((Get-PSReadLineOption).EditMode -eq 'Vi') {
             $script:viEditModeOverridden = $true
             Set-PSReadLineOption -EditMode Emacs
@@ -997,10 +974,8 @@ $null = New-Module -Name Warp-Module -ScriptBlock {
 
     function Warp-Finish-Bootstrap {
         param([decimal]$rcStartTime, [decimal]$rcEndTime)
-        # Sourcing the user's profiles can reconfigure PSReadLine out from under the bootstrap's
-        # own Warp-Precmd call, which ran before them: 'Set-PSReadLineOption -EditMode Vi' resets
-        # every key handler and so unbinds Warp's chords. Reconfiguring here, rather than waiting
-        # for the first prompt, also means the payload Warp-Bootstrapped sends below reports it.
+        # The profiles just sourced ran after the bootstrap's own Warp-Precmd, and setting the vi
+        # edit mode there unbinds Warp's chords by resetting every key handler.
         Warp-Configure-PSReadLine
 
         # This is the closest we can get in PowerShell to a proper preexec hook. We wrap the

crates/integration/src/bin/integration.rs

@@ -259,6 +259,7 @@ fn register_tests() -> HashMap<&'static str, BoxedBuilderFn> {
     register_test!(test_bash_bootstraps_with_prompt_command_array_that_sets_ps1);
     register_test!(test_zsh_bootstraps_with_nounset_option);
     register_test!(test_zsh_cursor_mode_vi_bindings_do_not_corrupt_commands);
+    register_test!(test_pwsh_vi_edit_mode_does_not_corrupt_commands);
     register_test!(test_ssh_wrapper_into_bash);
     register_test!(test_ssh_wrapper_into_zsh);
     register_test!(test_ssh_into_fish);

crates/integration/src/test/bootstrapping.rs

@@ -364,6 +364,42 @@ zle -N zle-line-init
         ))
 }
 
+/// Regression test for CORE-3804: a profile that selects PSReadLine's vi edit mode must not
+/// corrupt submitted commands. Warp's input-reporting and kill-buffer chords reach PSReadLine as
+/// a bare Escape plus a digit, which vi binds to ViCommandMode and DigitArgument, so before the
+/// fix a submitted `echo hello` arrived as `o hello`.
+pub fn test_pwsh_vi_edit_mode_does_not_corrupt_commands() -> Builder {
+    new_builder()
+        .set_should_run_test(|| {
+            let (starter, _) = current_shell_starter_and_version();
+            matches!(starter.shell_type(), shell::ShellType::PowerShell)
+        })
+        .with_setup(|utils| {
+            let dir = utils.test_dir();
+            write_rc_files_for_test(
+                dir,
+                "Set-PSReadLineOption -EditMode Vi",
+                [ShellRcType::PowerShell],
+            );
+        })
+        .with_step(wait_until_bootstrapped_single_pane_for_tab(0))
+        .with_step(clear_blocklist_to_remove_bootstrapped_blocks())
+        .with_step(execute_command_for_single_terminal_in_tab(
+            0,
+            "echo vi_edit_mode_ok".to_string(),
+            ExpectedExitStatus::Success,
+            "vi_edit_mode_ok",
+        ))
+        // The leading token is what vi command mode eats first, so a second command guards the
+        // failure mode where only part of the text survives.
+        .with_step(execute_command_for_single_terminal_in_tab(
+            0,
+            "Write-Output second_command_ok".to_string(),
+            ExpectedExitStatus::Success,
+            "second_command_ok",
+        ))
+}
+
 pub fn test_bash_bootstraps_with_prompt_command_array_that_sets_ps1() -> Builder {
     new_builder()
         .set_should_run_test(|| {

crates/integration/tests/integration/shell_integration_tests.rs

@@ -78,6 +78,8 @@ integration_tests! {
     // Tests zsh-specific behavior with nounset option.
     test_zsh_bootstraps_with_nounset_option,
     test_zsh_cursor_mode_vi_bindings_do_not_corrupt_commands,
+    // Tests PowerShell-specific behavior with PSReadLine's vi edit mode.
+    test_pwsh_vi_edit_mode_does_not_corrupt_commands,
 
     // Tests of ssh wrapper logic from bootstrap script.
     test_ssh_wrapper_into_bash,

script/presubmit

@@ -53,9 +53,6 @@ if command -v pwsh /dev/null 2>&1; then
     echo "Running PSScriptAnalyzer..."
     ./script/lint_powershell -ci
     echo "PsScriptAnalyzer succeeded..."
-    echo "Running pwsh bootstrap checks..."
-    ./script/test_pwsh_bootstrap -ci
-    echo "pwsh bootstrap checks succeeded..."
 elif [ "${GITHUB_ACTIONS}" == "true" ]; then
     # If we are in CI, and fail to find powershell, we should automatically fail
     echo "No powershell installation detected! Aborting!"