[DaveTseng2019]

Adds a chewing option shiftLetterSwitchToEnglish (default off). When it is on and no bopomofo is half typed (and no candidate window is open), Shift+letter switches to English mode and stays there. Chinese text already in the composition buffer stays, and the English text follows it. Tap Shift to return to Chinese.

Design: bopomofo has no letter case, so an uppercase letter typed in Chinese mode is a reliable signal that the user is starting an English word (a name, a sentence, an acronym). Shift+letter is that signal, so it is used as the trigger to switch to English.

Why: with easySymbolsWithShift on (the default), Shift+letter on an empty composition outputs an easy symbol and leaves the IME in Chinese mode. Typing an English word such as "Hello" in Chinese mode then gives a symbol followed by bopomofo garbage. Turning off easy symbols only makes the first letter English; the rest are still bopomofo.

• Chewing keeps Chinese text in the buffer until Enter, so requiring an empty composition would almost never switch mid-sentence. A half-typed bopomofo syllable or an open candidate window still blocks the switch.
• Respects upperCaseWithShift.
• Adds a checkbox under the Shift settings in the config tool.

Testing: tested by hand on Windows 11 (empty composition + Shift+H then ello gives "Hello"; tapping Shift returns to Chinese; Chinese text + full-width punctuation in the buffer, then Shift+H ello, switches to English and Enter commits the whole line; traced the key events in the backend to confirm the mode changes). No unit test added: chewing_ime has no unit test harness and needs libchewing and the TSF client.

Architecture and design by Dave Tseng. Implementation generated with AI assistance from Claude Code (Claude Opus 5.5).

🤖 Generated with Claude Code