Add '!edit' command to modify prompts in chat sessions using default editor (#969)

* Add '!edit' command to modify prompts in chat sessions

docs/changelog.md

@@ -419,6 +419,7 @@ This starts a chat session:
 ```
 Type 'exit' or 'quit' to exit
 Type '!multi' to enter multiple lines, then '!end' to finish
+Type '!edit' to open your default editor and modify the prompt.
 > Who are you?
 Hello! I'm just an AI, here to assist you with any questions you may have.
 My name is LLaMA, and I'm a large language model trained to provide helpful

docs/index.md

@@ -75,6 +75,7 @@ llm chat -m gpt-4o
 Chatting with gpt-4o
 Type 'exit' or 'quit' to exit
 Type '!multi' to enter multiple lines, then '!end' to finish
+Type '!edit' to open your default editor and modify the prompt.
 > Tell me a joke about a pelican
 Why don't pelicans like to tip waiters?
 

docs/usage.md

@@ -330,6 +330,7 @@ llm chat -t cheesecake
 Chatting with gpt-4
 Type 'exit' or 'quit' to exit
 Type '!multi' to enter multiple lines, then '!end' to finish
+Type '!edit' to open your default editor and modify the prompt
 > who are you?
 I am a sentient cheesecake, meaning I am an artificial
 intelligence embodied in a dessert form, specifically a
@@ -350,6 +351,7 @@ If your pasted text might itself contain a `!end` line, you can set a custom del
 Chatting with gpt-4
 Type 'exit' or 'quit' to exit
 Type '!multi' to enter multiple lines, then '!end' to finish
+Type '!edit' to open your default editor and modify the prompt.
 > !multi custom-end
  Explain this error:
 
@@ -362,6 +364,16 @@ urllib.error.URLError: <urlopen error [Errno 8] nodename nor servname provided,
  !end custom-end
 ```
 
+You can also use `!edit` to open your default editor and modify the prompt before sending it to the model.
+
+```
+Chatting with gpt-4
+Type 'exit' or 'quit' to exit
+Type '!multi' to enter multiple lines, then '!end' to finish
+Type '!edit' to open your default editor and modify the prompt.
+> !edit
+```
+
 ## Listing available models
 
 The `llm models` command lists every model that can be used with LLM, along with their aliases. This includes models that have been installed using {ref}`plugins <plugins>`.

llm/cli.py

@@ -905,6 +905,7 @@ def chat(
     click.echo("Chatting with {}".format(model.model_id))
     click.echo("Type 'exit' or 'quit' to exit")
     click.echo("Type '!multi' to enter multiple lines, then '!end' to finish")
+    click.echo("Type '!edit' to open your default editor and modify the prompt")
     in_multi = False
     accumulated = []
     end_token = "!end"
@@ -916,6 +917,15 @@ def chat(
             if len(bits) > 1:
                 end_token = "!end {}".format(" ".join(bits[1:]))
             continue
+        if prompt.strip() == "!edit":
+            edited_prompt = click.edit()
+            if edited_prompt is None:
+                click.echo("Editor closed without saving.", err=True)
+                continue
+            prompt = edited_prompt.strip()
+            if not prompt:
+                continue
+            click.echo(prompt)
         if in_multi:
             if prompt.strip() == end_token:
                 prompt = "\n".join(accumulated)

tests/test_chat.py

@@ -21,6 +21,7 @@ def test_chat_basic(mock_model, logs_db):
         "Chatting with mock"
         "\nType 'exit' or 'quit' to exit"
         "\nType '!multi' to enter multiple lines, then '!end' to finish"
+        "\nType '!edit' to open your default editor and modify the prompt"
         "\n> Hi"
         "\none world"
         "\n> Hi two"
@@ -86,6 +87,7 @@ def test_chat_basic(mock_model, logs_db):
         "Chatting with mock"
         "\nType 'exit' or 'quit' to exit"
         "\nType '!multi' to enter multiple lines, then '!end' to finish"
+        "\nType '!edit' to open your default editor and modify the prompt"
         "\n> Continue"
         "\ncontinued"
         "\n> quit"
@@ -134,6 +136,7 @@ def test_chat_system(mock_model, logs_db):
         "Chatting with mock"
         "\nType 'exit' or 'quit' to exit"
         "\nType '!multi' to enter multiple lines, then '!end' to finish"
+        "\nType '!edit' to open your default editor and modify the prompt"
         "\n> Hi"
         "\nI am mean"
         "\n> quit"