Places in code with 6 or more lines that are exactly the same.
Intro
- For duplication, we look at places in code where there are 6 or more lines of code that are exactly the same.
- Before duplication is calculated, the code is cleaned to remove empty lines, comments, and frequently duplicated constructs such as imports.
- You should aim at having as little as possible (<5%) of duplicated code as high-level of duplication can lead to maintenance difficulties, poor factoring, and logical contradictions.
- To learn more about duplications and techniques for eliminating duplication, Sokrates recommends the following resources:
- Avoid Repetition, MartinFlower.com (IEEE Software article)
- Refactoring duplicated code, sourcemaking.com
- Beck Design Rules, MartinFowler.com
- DRY (Don't Repeat Yourself) Principle, Wikipedia
- The Cut-and-Paste Programming Software Development Anti-Pattern, sourcemaking.com
- Code Smells / Duplicated Code, Jeff Atwood, codinghorror.com:
- "Duplicated code is the bane of software development. Stamp out duplication whenever possible. You should always be on the lookout for more subtle cases of near-duplication, too. Don't Repeat Yourself!"
- Reducing Coupling, MartinFlower.com (IEEE Software article):
- "There are several ways to describe coupling, but it boils down to this: If changing one module in a program requires changing another module, then coupling exists. ... Duplication always implies coupling, because changing one piece of duplicate code implies changing the other."
Duplication Overall
- 28% duplication:
- 10,472 cleaned lines of cleaned code (without empty lines, comments, and frequently duplicated constructs such as imports)
- 2,937 duplicated lines
- 1,548 duplicates
Duplication per Extension
Duplication per Component (primary)
Duplication Between Components (50+ lines)
Open 3D force graph...
Show more details on duplication between components...
From Component
--> To Component
Duplicated
Lines
File Pairs
Details
cpp/AdvancedColorImages/AdvancedColorImages (31%)
--> cpp/VirtualSurfaces/VirtualSurfaces (43%)
730
8 file pairs
details...
cpp/AdvancedColorImages/AdvancedColorImages (13%)
--> cpp/HelloComposition/HelloComposition (23%)
303
3 file pairs
details...
cpp/HelloComposition/HelloComposition (17%)
--> cpp/VirtualSurfaces/VirtualSurfaces (13%)
222
2 file pairs
details...
cpp/HelloComposition/HelloComposition (13%)
--> cpp/HelloVectors (2%)
180
1 file pair
details...
cpp/HelloVectors (2%)
--> cpp/VirtualSurfaces/VirtualSurfaces (10%)
178
1 file pair
details...
dotnet/WPF/AcrylicEffect (26%)
--> dotnet/WPF/VisualLayerIntegration (7%)
160
3 file pairs
details...
dotnet/WinForms/HelloComposition (44%)
--> dotnet/WinForms/VisualLayerIntegration (10%)
146
3 file pairs
details...
dotnet/WPF/HelloComposition (31%)
--> dotnet/WinForms/HelloComposition (44%)
146
3 file pairs
details...
cpp/AdvancedColorImages/AdvancedColorImages (6%)
--> cpp/HelloVectors (1%)
146
1 file pair
details...
dotnet/WinForms/AcrylicEffect (27%)
--> dotnet/WinForms/HelloComposition (39%)
130
3 file pairs
details...
dotnet/WPF/AcrylicEffect (19%)
--> dotnet/WinForms/AcrylicEffect (25%)
120
3 file pairs
details...
cpp/HelloVectors (1%)
--> cpp/ScreenCaptureforHWND/ScreenCaptureforHWND (9%)
118
2 file pairs
details...
cpp/ScreenCaptureforHWND/ScreenCaptureforHWND (8%)
--> cpp/VirtualSurfaces/VirtualSurfaces (6%)
104
1 file pair
details...
cpp/HelloComposition/HelloComposition (8%)
--> cpp/ScreenCaptureforHWND/ScreenCaptureforHWND (8%)
104
1 file pair
details...
dotnet/WinForms/AcrylicEffect (21%)
--> dotnet/WinForms/VisualLayerIntegration (7%)
102
3 file pairs
details...
dotnet/WPF/HelloComposition (18%)
--> dotnet/WinForms/VisualLayerIntegration (6%)
88
1 file pair
details...
dotnet/WPF/HelloComposition (18%)
--> dotnet/WinForms/AcrylicEffect (18%)
86
1 file pair
details...
cpp/AdvancedColorImages/AdvancedColorImages (3%)
--> cpp/ScreenCaptureforHWND/ScreenCaptureforHWND (6%)
82
1 file pair
details...
dotnet/WPF/AcrylicEffect (8%)
--> dotnet/WPF/HelloComposition (11%)
54
2 file pairs
details...
dotnet/WPF/HelloComposition (10%)
--> dotnet/WPF/VisualLayerIntegration (2%)
50
2 file pairs
details...
| From Component --> To Component |
Duplicated Lines |
File Pairs | Details |
|---|---|---|---|
| cpp/AdvancedColorImages/AdvancedColorImages (31%) --> cpp/VirtualSurfaces/VirtualSurfaces (43%) |
730 | 8 file pairs | details... |
| cpp/AdvancedColorImages/AdvancedColorImages (13%) --> cpp/HelloComposition/HelloComposition (23%) |
303 | 3 file pairs | details... |
| cpp/HelloComposition/HelloComposition (17%) --> cpp/VirtualSurfaces/VirtualSurfaces (13%) |
222 | 2 file pairs | details... |
| cpp/HelloComposition/HelloComposition (13%) --> cpp/HelloVectors (2%) |
180 | 1 file pair | details... |
| cpp/HelloVectors (2%) --> cpp/VirtualSurfaces/VirtualSurfaces (10%) |
178 | 1 file pair | details... |
| dotnet/WPF/AcrylicEffect (26%) --> dotnet/WPF/VisualLayerIntegration (7%) |
160 | 3 file pairs | details... |
| dotnet/WinForms/HelloComposition (44%) --> dotnet/WinForms/VisualLayerIntegration (10%) |
146 | 3 file pairs | details... |
| dotnet/WPF/HelloComposition (31%) --> dotnet/WinForms/HelloComposition (44%) |
146 | 3 file pairs | details... |
| cpp/AdvancedColorImages/AdvancedColorImages (6%) --> cpp/HelloVectors (1%) |
146 | 1 file pair | details... |
| dotnet/WinForms/AcrylicEffect (27%) --> dotnet/WinForms/HelloComposition (39%) |
130 | 3 file pairs | details... |
| dotnet/WPF/AcrylicEffect (19%) --> dotnet/WinForms/AcrylicEffect (25%) |
120 | 3 file pairs | details... |
| cpp/HelloVectors (1%) --> cpp/ScreenCaptureforHWND/ScreenCaptureforHWND (9%) |
118 | 2 file pairs | details... |
| cpp/ScreenCaptureforHWND/ScreenCaptureforHWND (8%) --> cpp/VirtualSurfaces/VirtualSurfaces (6%) |
104 | 1 file pair | details... |
| cpp/HelloComposition/HelloComposition (8%) --> cpp/ScreenCaptureforHWND/ScreenCaptureforHWND (8%) |
104 | 1 file pair | details... |
| dotnet/WinForms/AcrylicEffect (21%) --> dotnet/WinForms/VisualLayerIntegration (7%) |
102 | 3 file pairs | details... |
| dotnet/WPF/HelloComposition (18%) --> dotnet/WinForms/VisualLayerIntegration (6%) |
88 | 1 file pair | details... |
| dotnet/WPF/HelloComposition (18%) --> dotnet/WinForms/AcrylicEffect (18%) |
86 | 1 file pair | details... |
| cpp/AdvancedColorImages/AdvancedColorImages (3%) --> cpp/ScreenCaptureforHWND/ScreenCaptureforHWND (6%) |
82 | 1 file pair | details... |
| dotnet/WPF/AcrylicEffect (8%) --> dotnet/WPF/HelloComposition (11%) |
54 | 2 file pairs | details... |
| dotnet/WPF/HelloComposition (10%) --> dotnet/WPF/VisualLayerIntegration (2%) |
50 | 2 file pairs | details... |
Longest Duplicates
The list of 20 longest duplicates.
| Size | # | Folders | Files | Lines | Code |
|---|---|---|---|---|---|
| 53 | x 2 | cpp/HelloComposition/HelloCompositioncpp/VirtualSurfaces/VirtualSurfaces | vcxproj HelloComposition.vcxprojVirtualSurfaces.vcxproj |
26:93 (35%)26:93 (36%) | view |
| 37 | x 2 | dotnet/WinForms/AcrylicEffect/AcrylicEffectdotnet/WinForms/HelloComposition/HelloComposition |  CompositionHostForm.csCompositionHost.cs |
83:141 (51%)76:174 (49%) | view |
| 37 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces |  WinComp.cppWinComp.cpp |
140:212 (27%)140:212 (38%) | view |
| 35 | x 2 | cpp/ScreenCaptureforHWND/ScreenCaptureforHWNDcpp/VirtualSurfaces/VirtualSurfaces | vcxproj ScreenCaptureforHWND.vcxprojVirtualSurfaces.vcxproj |
28:72 (28%)28:72 (24%) | view |
| 35 | x 2 | cpp/HelloComposition/HelloCompositioncpp/ScreenCaptureforHWND/ScreenCaptureforHWND | vcxproj HelloComposition.vcxprojScreenCaptureforHWND.vcxproj |
28:72 (23%)28:72 (28%) | view |
| 33 | x 2 | dotnet/WPF/AcrylicEffect/AcrylicEffectdotnet/WPF/VisualLayerIn.../VisualLayerIntegration | User32.csUser32.cs |
1:73 (100%)1:73 (100%) | view |
| 31 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces | vcxproj AdvancedColorImages.vcxprojVirtualSurfaces.vcxproj |
116:152 (21%)117:153 (21%) | view |
| 30 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces | vcxproj AdvancedColorImages.vcxprojVirtualSurfaces.vcxproj |
52:92 (20%)52:92 (20%) | view |
| 30 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/HelloComposition/HelloComposition | vcxproj AdvancedColorImages.vcxprojHelloComposition.vcxproj |
52:92 (20%)52:92 (20%) | view |
| 26 | x 2 | cpp/HelloComposition/HelloCompositioncpp/HelloVectors | vcxproj HelloComposition.vcxprojHelloVectors_win32_cpp.vcxproj |
28:58 (17%)30:60 (16%) | view |
| 26 | x 2 | cpp/HelloVectorscpp/ScreenCaptureforHWND/ScreenCaptureforHWND | vcxproj HelloVectors_win32_cpp.vcxprojScreenCaptureforHWND.vcxproj |
30:60 (16%)28:58 (20%) | view |
| 26 | x 2 | cpp/HelloVectorscpp/VirtualSurfaces/VirtualSurfaces | vcxproj HelloVectors_win32_cpp.vcxprojVirtualSurfaces.vcxproj |
30:60 (16%)28:58 (17%) | view |
| 23 | x 2 | dotnet/WinForms/HelloComposition/HelloCompositiondotnet/WinForms/VisualLa.../VisualLayerIntegration | CompositionHost.csCompositionHost.cs |
76:129 (30%)138:191 (22%) | view |
| 23 | x 2 | dotnet/WinForms/AcrylicEffect/AcrylicEffectdotnet/WinForms/VisualLa.../VisualLayerIntegration | CompositionHostForm.csCompositionHost.cs |
83:115 (31%)138:191 (22%) | view |
| 22 | x 2 | dotnet/WPF/HelloComposition/HelloCompositiondotnet/WinForms/AcrylicEffect/AcrylicEffect | CompositionHost.csCompositionHostForm.cs |
127:178 (20%)83:113 (30%) | view |
| 22 | x 2 | dotnet/WPF/HelloComposition/HelloCompositiondotnet/WinForms/HelloComposition/HelloComposition | CompositionHost.csCompositionHost.cs |
127:178 (20%)76:127 (29%) | view |
| 22 | x 2 | dotnet/WPF/HelloComposition/HelloCompositiondotnet/WinForms/VisualLa.../VisualLayerIntegration | CompositionHost.csCompositionHost.cs |
127:178 (20%)138:189 (21%) | view |
| 20 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces | TileDrawingManager.cppTileDrawingManager.cpp |
90:144 (25%)90:144 (26%) | view |
| 19 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces | filters AdvancedColorImages.vcxproj.filtersVirtualSurfaces.vcxproj.filters |
1:25 (37%)1:25 (41%) | view |
| 18 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/HelloComposition/HelloComposition | AdvancedColorImages.cppHelloComposition.cpp |
261:288 (12%)175:202 (18%) | view |
Duplicated Units
The list of top 16 duplicated units.
| Size | # | Folders | Files | Lines | Code |
|---|---|---|---|---|---|
| 20 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces | WinComp.cppWinComp.cpp |
175:202 175:202 | view |
| 17 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces | DirectXTileRenderer.cppDirectXTileRenderer.cpp |
152:170 182:200 | view |
| 16 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/HelloComposition/HelloComposition | AdvancedColorImages.cppHelloComposition.cpp |
272:289 186:203 | view |
| 13 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces | DirectXTileRenderer.cppDirectXTileRenderer.cpp |
244:263 277:296 | view |
| 12 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces | DirectXTileRenderer.cppDirectXTileRenderer.cpp |
117:133 133:149 | view |
| 12 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces | TileDrawingManager.cppTileDrawingManager.cpp |
193:207 180:194 | view |
| 12 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces | WinComp.cppWinComp.cpp |
26:41 26:41 | view |
| 12 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces | WinComp.cppWinComp.cpp |
152:168 152:168 | view |
| 12 | x 2 | cpp/HelloVectorscpp/ScreenCaptureforHWND/ScreenCaptureforHWND |  desktopcompositionwindow.hmain.cpp |
36:50 27:41 | view |
| 11 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces | WinComp.cppWinComp.cpp |
76:93 76:93 | view |
| 10 | x 2 | dotnet/WinForms/AcrylicEffect/AcrylicEffectdotnet/WinForms/HelloComposition/HelloComposition | CompositionHostForm.csCompositionHost.cs |
111:125 125:150 | view |
| 9 | x 3 | dotnet/WPF/HelloComposition/HelloCompositiondotnet/WinForms/HelloComposition/HelloCompositiondotnet/WinForms/VisualLa.../VisualLayerIntegration | CompositionHost.csCompositionHost.csCompositionHost.cs |
99:109 40:50 65:75 | view |
| 8 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces | WinComp.cppWinComp.cpp |
100:110 100:110 | view |
| 7 | x 2 | cpp/HelloVectorscpp/ScreenCaptureforHWND/ScreenCaptureforHWND | desktopcompositionwindow.hmain.cpp |
207:215 43:51 | view |
| 7 | x 3 | dotnet/WinForms/AcrylicEffect/AcrylicEffectdotnet/WinForms/HelloComposition/HelloCompositiondotnet/WinForms/VisualLa.../VisualLayerIntegration | Form1.Designer.csForm1.Designer.csForm1.Designer.cs |
14:21 14:21 14:21 | view |
| 6 | x 2 | cpp/AdvancedColorImages/AdvancedColorImagescpp/VirtualSurfaces/VirtualSurfaces | TileDrawingManager.cppTileDrawingManager.cpp |
112:120 112:120 | view |