Introducing Rubberduck v2.3.0

Version 2.2.0 was released in April 2018. Well over 1,700 commits and 2,185 modified files later, Rubberduck is now more stable than ever, and well overdue for a new release. November 25th will see Rubberduck 2.3 issued – as of this writing, we’re ironing a few wrinkles, but everything looks like we’re on track to release some time this Sunday.

A tremendous amount of effort went into the core, the engine, and the brain: the number of situations causing inspection false positives is on a serious decline, and we’ve taken very important steps towards ensuring proper tear-down of every component. Rubberduck 2.3 is by far the most stable release to date, and all the invisible work lays the foundation for the very exciting things to come.

We’re all extremely proud to present the results of so many months of hard work! Here’s a non-exhaustive overview of the new features (versus 2.2.0).

Official VB6 IDE Support

As of v2.3.0 (with special thanks to @mansellan), Rubberduck officially works in Visual Studio 6.0, the glorious, the… legendary VB6 IDE.

That’s right: code inspections, code metrics, all navigation enhancements, unit testing, refactorings, …all your favorite Rubberduck features, in the Visual Basic 6.0 editor.

This is without a doubt the biggest improvement to ever come to the VB6 IDE this century, from an open-source project.

As is the case for VBA hosts, if you already have Smart Indenter installed, Rubberduck will detect the legacy 32-bit add-in and prompt to import your settings – note that configuring Rubberduck’s indenter will not affect your Smart Indenter settings.

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Autocompletion Enhancements

Rubberduck now changes how typing code in the editor feels. If you ever edited VBA/VB6 code in Notepad++ (let alone VB.NET code in the latest Visual Studio), you know that the VBE shows its age when you type a " double quote or open a ( parenthesis. With Rubberduck, typing code in the VBE will now feel radically different than without, in a very good way. A new dedicated settings page makes it easy to enable/disable each feature separately, and leaves room for future customization and enhancements.

Due to its rather invasive nature, a design decision was made to ship autocompletion features disabled by default; these features must be enabled manually, in the autocompletion settings tab of Rubberduck’s “Settings” dialog:

Self-Closing Pairs

It’s hard to describe everything enabling SCP completion does. A picture is worth a thousand words, so… how about seeing them in action?

When {BACKSPACE} is pressed and the caret immediately follows any opening token, Rubberduck attempts to locate and remote the matching closing token, wherever it is on the current logical line of code – nested or not.

Smart Concatenation

When enabled, Rubberduck will step in when the {ENTER} key is pressed while the caret is inside a string literal, to automatically append ” & _” to the current line.

The feature can also be configured so that when the {CTRL} key is held down when {ENTER} is pressed, ” & vbNewLine & _” will be appended to the current line.

{BACKSPACE} cleanly reverts smart-concatenation when the caret is on the last line of the logical code line and the caret line contains nothing but the opening & closing quotes.

Block Completion

Block completion will be implemented early in the 2.3.x cycle: these settings have no effect whatsoever for now.

The vision for this feature, is to capture “trigger” keywords (e.g. For), select them; if {TAB} or {ENTER} is pressed (as configured) when the “trigger” is selected (among other conditions), then the block expands, and Rubberduck automatically highlights a placeholder expression; hitting {TAB} again selects the next placeholder, {SHIFT}+{TAB} the previous. Providing a value for the last placeholder places the caret inside the block, indented as per indenter settings.

Auto-correct

Later in the 2.3.x cycle, auto-completion will be further enhanced with an “auto-correct” feature, which will enable automatically expanding e.g. foo++ into foo = foo + 1, among other ideas… including automatic fixing of a configurable list of “frequent typos”.

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New Inspections

As with every new Rubberduck release, the team implemented a number of new inspections. This release introduces an internal API for code path analysis, which allows us to start implementing the more involved inspections on our plate!

These new inspections bring the total number to 75!

AssignmentNotUsed

The first inspection to leverage code path analysis, will now flag this code:

foo = 42 ' <~ value is never used
foo = 10
Debug.Print foo

When an assignment is subsequently discarded before the stored value is accessed, Rubberduck will notify about the redundant assignment, as a code quality issue.

DuplicatedAnnotation

This inspection, spliced from the existing “illegal annotation” inspection, helps validate/sanitize Rubberduck annotations – for example, contradicting @Folder annotations:

'@Folder("Foo")
'@Folder("Bar")

ExcelUdfNameIsValidCellReference

An Excel-specific inspection that flags public functions that are visible as worksheet user-defined functions (UDF), but shadowed by a cell reference. This inspection is particularly useful with recent 64-bit versions of Microsoft Excel, where 16,384 columns effectively reserve every 3-letter combination up to “XFC”.

Public Function Foo123() As String
'FOO123 is a valid cell reference; function cannot be invoked!
End Function

This first iteration only inspects public functions in standard procedural modules.

IsMissingOnInappropriateArgument

A rather specific inspection validating usages of IsMissing, flagging instances where the function is given a non-Variant argument.

Public Sub DoSomething(Optional ByVal foo As String)
    If IsMissing(foo) Then ' condition is always false
    End If
End Sub

IsMissingWithNonArgumentParameter

Another inspection validating usages of IsMissing, flagging instances where the function is given a non-parameter argument.

Public Sub DoSomething()
    Dim foo As Variant
    If IsMissing(foo) Then ' condition is always false
    End If
End Sub

ObsoleteCallingConvention

CDecl calling convention isn’t supported on Windows; Declare statements using it should be wrapped with conditional compilation directives so as to only compile in a Mac environment.

Private Declare Sub Beep CDecl Lib "kernel32" (dwFreq As Any, dwDuration As Any)

ObsoleteMemberUsage

Rubberduck 2.3 introduces a new @Obsolete annotation, which can be used for annotating “obsolete” procedures – the inspection flags usages of procedures marked with this annotation.

OnLocalError

The Local token is redundant in On Error statements. This inspection flags usages.

Private Sub DoSomething()
    On Local Error GoTo ErrHandler
    '...
    Exit Sub
ErrHandler:
End Sub

The rationale being, runtime errors are always local; the two syntaxes look different but do exactly the same thing.

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v2.3.x

There are a number of features that were intended to be developed for 2.2.x, that didn’t make it into this release – not because the ideas were dropped, but because of mere time constraints. The add/remove references dialog is one such feature. Keep an eye out on 2.3.x pre-release builds and announcements; the v2.4 announcement will recap everything that happened in 2.3.x, but every new feature will very likely see its own dedicated blog post as it is merged and pre-released.