Fix bug in expression display when determining if a pointer should be treated as a string

[paulmaybee]

Summary

Currently if the "first child" of the pointer is a char type then the pointer is displayed as a string. This test succeeds incorrectly when the pointer is to a structured type with a char type as its first field. Fix this by switching the test to retrieve the pointee type and checking that it is a char type.

[ki.stfu]

It looks strangely for me. If structure has the first element of type char then GetChildAtIndex(0) will refer to this element and GetType().GetBasicType() will be char. But if we have a pointer to that structure then I suppose GetChildAtIndex(0) will not be equal to the first element of structure. From my point of view, it should relate to this structure entirely, but not to its first element.

[ki.stfu]

Add add a test case for this please.

[paulmaybee]

Add test case

[ki.stfu]

See my inline comments.

test/tools/lldb-mi/variable/main.cpp

70–76 ↗

(On Diff #30590)

Use clang-format for formatting please.

83 ↗

(On Diff #30590)

a memory leak. just allocate it on the stack and then use "&nstr"

tools/lldb-mi/MICmnLLDBUtilSBValue.cpp

139–142

Please wrap it into IsPointeeCharType():

if (m_bHandleCharType && IsPointeeCharType())

364

Change to "Static":

// Type:    Static.

404

Add IsPointeeCharType() function after IsFirstChildCharType():

//++ ------------------------------------------------------------------------------------
// Details: Retrieve the flag stating whether pointee object of *this object is a char
//          type or some other type. Returns false if there are not children. Char type
//          can be signed or unsigned.
// Type:    Method.
// Args:    None.          
// Return:  bool    - True = Yes is a char type, false = some other type.
// Throws:  None.
//--
bool
CMICmnLLDBUtilSBValue::IsPointeeCharType(void) const
{
    const MIuint nChildren = m_rValue.GetNumChildren();

    // Is it a basic type
    if (nChildren == 0)
        return false;

    const lldb::BasicType eType = m_rValue.GetType().GetPointeeType().GetBasicType();
    return IsCharBasicType(eType);
}

tools/lldb-mi/MICmnLLDBUtilSBValue.h

57

Add

bool IsPointeeCharType(void) const;

after these lines:

CMIUtilString GetTypeName(void) const;
CMIUtilString GetTypeNameDisplay(void) const;
bool IsCharType(void) const;
bool IsFirstChildCharType(void) const;

60–61

Move to separate section:

  // Statics:
private:
  static bool IsCharBasicType(lldb::BasicType eType);

[paulmaybee]

Add IsPointeeCharType

[ki.stfu]

Add a section title and go ahead.

tools/lldb-mi/MICmnLLDBUtilSBValue.h

61

Forgot a section title:

  // Statics:
private:
  static bool IsCharBasicType(lldb::BasicType eType);

[paulmaybee]

Added the section title.
If you are ok with this now then can you please check it in?

Thanks.

tools/lldb-mi/MICmnLLDBUtilSBValue.h

     CMIUtilString GetSimpleValueCStringPointer(void) const;
     CMIUtilString GetSimpleValueCStringArray(void) const;
     bool GetCompositeValue(const bool vbPrintFieldNames, CMICmnMIValueTuple &vwrMiValueTuple, const MIuint vnDepth = 1) const;
-
+    static bool IsCharBasicType(lldb::BasicType eType);
+    
     // Attributes:
   private:
     lldb::SBValue &m_rValue;

tools/lldb-mi/MICmnLLDBUtilSBValue.cpp

     }
     else if (IsPointerType())
     {
-        if (m_bHandleCharType && IsFirstChildCharType())
+        const lldb::BasicType eType = m_rValue.GetType().GetPointeeType().GetBasicType();
+
+        if (m_bHandleCharType && IsCharBasicType(eType))
         {
             vwrValue = GetSimpleValueCStringPointer();
             return MIstatus::success;

 }
 
 //++ ------------------------------------------------------------------------------------
-// Details: Retrieve the flag stating whether this value object is a char type or some
-//          other type. Char type can be signed or unsigned.
+// Details: Check that basic type is a char type. Char type can be signed or unsigned.
 // Type:    Method.
-// Args:    None.
+// Args:    eType   - type to check
 // Return:  bool    - True = Yes is a char type, false = some other type.
 // Throws:  None.
 //--
 bool
-CMICmnLLDBUtilSBValue::IsCharType(void) const
+CMICmnLLDBUtilSBValue::IsCharBasicType(lldb::BasicType eType)
 {
-    const lldb::BasicType eType = m_rValue.GetType().GetBasicType();
     switch (eType)
     {
         case lldb::eBasicTypeChar:

 }
 
 //++ ------------------------------------------------------------------------------------
+// Details: Retrieve the flag stating whether this value object is a char type or some
+//          other type. Char type can be signed or unsigned.
+// Type:    Method.
+// Args:    None.
+// Return:  bool    - True = Yes is a char type, false = some other type.
+// Throws:  None.
+//--
+bool
+CMICmnLLDBUtilSBValue::IsCharType(void) const
+{
+    const lldb::BasicType eType = m_rValue.GetType().GetBasicType();
+    return IsCharBasicType(eType);
+}
+
+
+//++ ------------------------------------------------------------------------------------
 // Details: Retrieve the flag stating whether first child value object of *this object is
 //          a char type or some other type. Returns false if there are not children. Char
 //          type can be signed or unsigned.