IntelliSense Controller

[sharwell]

This is a high-level issue to discuss the requirements for supporting IntelliSense in custom extensions, with a particular focus on operations which use an IIntellisenseController (for other IntelliSense commands see #44). The controller works closely with a custom command filter to ensure operations which modify keyboard behavior work properly.

IntelliSense Operations

• Code completion (ICompletionSession)
• Member info (ISignatureHelpSession)
• Quick info (IQuickInfoSession)
• Smart tags (ISmartTagSession)

❓ Should a single IIntellisenseController instance handle all of these items?

Code completion

• Need to distinguish between the manner in which code completion was instantiated
  • Triggered by typing Ctrl+Space (Edit.CompleteWord)
  • Triggered by Edit.ListMembers (like Edit.CompleteWord, but does not automatically commit a unique result)
  • Automatically triggered by typing a character
    • ❓ Should this further distinguish between context info (e.g. typing the first letter of a variable in the current lexical scope) and member info (e.g. typing a . for member selection)?
  • Automatically triggered by typing a space (e.g. the space after typing override in C#)
• Need to handle code snippets (IVsExpansionManager)
• Need to handle the Edit.ToggleCompletionMode command
• ❓ Need to handle the Edit.OverrideMembers command
• Listens to some keystrokes
• Handles some keystrokes (i.e. not passed on to the editor)

Member info

• Need to distinguish between the manner in which member info was instantiated
  • Triggered by typing Ctrl+Shift+Space (Edit.ParameterInfo)
  • Automatically triggered by typing a character (e.g. ()
• Listens to keyboard commands, but does not handle any keystrokes

Quick info

• ❓ Can be triggered by hovering the mouse or Edit.QuickInfo, but do we need to distinguish?

Smart tags

TBD