Rubberduck - SuspiciousPredeclaredInstanceAccess

New This feature is currently only available in pre-release builds (or the xmldoc asset doesn’t yet exist on main!).

Inspection type: CodeQualityIssues

Default severity: Warning

Reasoning

While a stateful default instance might be intentional, when it isn't it's easily a source of bugs. Use the Me qualifier to explicitly refer to the current instance and eliminate any ambiguity. Global state accidentally stored in a class' default instance is not shared by all other instances of that class

Quick-Fixes

The following quick-fixes are available for this inspection:

IgnoreOnce: Adds an '@Ignore annotation to ignore a specific inspection result. Applicable to all inspections whose results can be annotated in a module.
IgnoreInModule: Adds an '@IgnoreModule annotation to ignore a inspection results for a specific inspection inside a whole module. Applicable to all inspections whose results can be annotated in a module.
ReplaceQualifierWithMe: Replaces an explicit qualifier with 'Me'.

Examples

Each example is a self-contained MCVE showing the feature in a single specific scenario.

Standard Module

Named Module1 by default, these are general-purpose standard procedural modules.

Class Module

Named Class1 by default, these modules define the default interface for an object of that type.

Predeclared Class

A class module with its VB_PredeclaredId attribute set to True (with or without a @PredeclaredId annotation).

Interface Module

Abstract interfaces are class modules (with or without an @Interface annotation) whose default interface is not a class type intended to be instantiated.

UserForm Module

A predeclared class with a design-time visual designer using the MSForms UI framework.

Document Module

Owned by the host application, these class modules belong to the host document and may handle various events fired by the host application.

The following code should trigger this inspection:

Module1

Option Explicit
Public Sub Test1()
    UserForm1.Show ' the default instance is being shown
End Sub
Public Sub Test2()
    With New UserForm1
        .Show ' a new instance is being shown
    End With
End Sub

UserForm1

Option Explicit
Private ClickCount As Long
Private Sub CommandButton1_Click()
ClickCount = ClickCount + 1
UserForm1.TextBox1.Text = ClickCount ' only TextBox1 on the default instance is affected
End Sub