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
- 19% duplication:
- 52,190 cleaned lines of cleaned code (without empty lines, comments, and frequently duplicated constructs such as imports)
- 10,216 duplicated lines
- 1,156 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
lib/common (10%)
--> lib/legacy (3%)
760
27 file pairs
details...
build/VS2010 (25%)
--> lib/dll (227%)
647
7 file pairs
details...
lib/decompress (4%)
--> lib/legacy (1%)
346
10 file pairs
details...
contrib/linux-kernel (12%)
--> lib/common (1%)
76
1 file pair
details...
lib/common (<1%)
--> lib/decompress (<1%)
60
1 file pair
details...
| From Component --> To Component |
Duplicated Lines |
File Pairs | Details |
|---|---|---|---|
| lib/common (10%) --> lib/legacy (3%) |
760 | 27 file pairs | details... |
| build/VS2010 (25%) --> lib/dll (227%) |
647 | 7 file pairs | details... |
| lib/decompress (4%) --> lib/legacy (1%) |
346 | 10 file pairs | details... |
| contrib/linux-kernel (12%) --> lib/common (1%) |
76 | 1 file pair | details... |
| lib/common (<1%) --> lib/decompress (<1%) |
60 | 1 file pair | details... |
Longest Duplicates
The list of 50 longest duplicates.
| Size | # | Folders | Files | Lines | Code |
|---|---|---|---|---|---|
| 308 | x 2 | lib/legacylib/legacy | 2602:3207 (19%)2241:2848 (22%) | view | |
| 229 | x 2 | lib/legacylib/legacy | 64:812 (14%)65:814 (16%) | view | |
| 227 | x 2 | lib/legacylib/legacy | 1178:1635 (14%)1179:1632 (16%) | view | |
| 206 | x 2 | lib/legacylib/legacy | 1638:1953 (12%)1635:1950 (14%) | view | |
| 147 | x 2 | lib/legacylib/legacy | 1958:2187 (9%)1955:2184 (10%) | view | |
| 144 | x 2 | lib/legacylib/legacy | 1728:1933 (10%)1879:2084 (8%) | view | |
| 144 | x 2 | lib/legacylib/legacy | 1731:1936 (8%)1879:2084 (8%) | view | |
| 108 | x 2 | lib/legacylib/legacy | 2090:2241 (7%)2237:2388 (6%) | view | |
| 105 | x 2 | lib/legacylib/legacy | 1117:1298 (7%)1094:1275 (6%) | view | |
| 100 | x 2 | lib/legacylib/legacy | 2920:3050 (6%)2687:2817 (6%) | view | |
| 100 | x 2 | lib/legacylib/legacy | 2561:2691 (7%)2687:2817 (6%) | view | |
| 87 | x 2 | lib/legacylib/legacy | 3337:3476 (5%)2978:3118 (6%) | view | |
| 84 | x 2 | lib/legacylib/legacy | 59:319 (4%)220:474 (3%) | view | |
| 84 | x 2 | build/VS2010/libzstd-dllbuild/VS2010/libzstd | 1:90 (40%)1:90 (41%) | view | |
| 81 | x 2 | lib/legacylib/legacy | 1939:2086 (5%)2089:2234 (4%) | view | |
| 78 | x 2 | lib/legacylib/legacy | 1178:1297 (4%)1156:1275 (4%) | view | |
| 76 | x 2 | lib/legacylib/legacy | 3209:3324 (4%)2850:2965 (5%) | view | |
| 75 | x 2 | build/VS2010/fullbench-dlllib/dll/example | 1:95 (50%)1:95 (52%) | view | |
| 74 | x 2 | lib/legacylib/legacy | 1958:2089 (4%)2105:2234 (4%) | view | |
| 71 | x 2 | lib/legacylib/legacy | 2093:2187 (4%)2237:2331 (4%) | view | |
| 70 | x 2 | lib/legacylib/legacy | 65:257 (5%)29:228 (4%) | view | |
| 70 | x 2 | lib/legacylib/legacy | 64:256 (4%)29:228 (4%) | view | |
| 58 | x 2 | lib/legacylib/legacy | 1516:1629 (3%)1673:1779 (3%) | view | |
| 58 | x 2 | lib/legacylib/legacy | 1513:1626 (4%)1673:1779 (3%) | view | |
| 55 | x 2 | build/VS2010/datagenbuild/VS2010/fullbench | 87:157 (42%)87:157 (30%) | view | |
| 54 | x 2 | lib/legacylib/legacy | 1317:1412 (3%)1296:1391 (3%) | view | |
| 54 | x 2 | lib/legacylib/legacy | 1316:1411 (3%)1296:1391 (3%) | view | |
| 53 | x 2 | build/VS2010/fullbench-dllbuild/VS2010/fullbench | 25:92 (35%)25:92 (29%) | view | |
| 53 | x 2 | build/VS2010/fullbenchlib/dll/example | 25:92 (29%)25:92 (37%) | view | |
| 52 | x 2 | lib/legacylib/legacy | 305:416 (3%)578:684 (3%) | view | |
| 52 | x 2 | lib/legacylib/legacy | 307:419 (3%)578:684 (3%) | view | |
| 50 | x 2 | lib/legacylib/legacy | 1638:1727 (3%)1787:1876 (3%) | view | |
| 50 | x 2 | lib/legacylib/legacy | 1635:1724 (3%)1787:1876 (3%) | view | |
| 44 | x 2 | lib/legacylib/legacy | 420:546 (2%)687:817 (2%) | view | |
| 44 | x 2 | lib/legacylib/legacy | 423:548 (3%)687:817 (2%) | view | |
| 42 | x 2 | lib/legacylib/legacy | 644:746 (3%)817:919 (2%) | view | |
| 42 | x 2 | lib/legacylib/legacy | 642:744 (2%)817:919 (2%) | view | |
| 42 | x 2 | lib/legacylib/legacy | 1281:1329 (2%)1225:1273 (1%) | view | |
| 37 | x 2 | lib/legacylib/legacy | 1101:1173 (2%)1102:1174 (2%) | view | |
| 36 | x 2 | lib/legacylib/legacy | 1588:1637 (3%)2577:2626 (2%) | view | |
| 36 | x 2 | lib/legacylib/legacy | 1588:1637 (3%)2936:2985 (2%) | view | |
| 36 | x 2 | lib/legacylib/legacy | 1588:1637 (3%)2703:2752 (2%) | view | |
| 35 | x 2 | lib/legacylib/legacy | 2009:2048 (1%)2391:2430 (1%) | view | |
| 35 | x 2 | lib/legacylib/legacy | 1731:1770 (2%)2093:2132 (2%) | view | |
| 35 | x 2 | lib/legacylib/legacy | 2143:2182 (1%)2518:2557 (1%) | view | |
| 35 | x 2 | lib/legacylib/legacy | 1731:1770 (2%)2090:2129 (2%) | view | |
| 35 | x 2 | lib/legacylib/legacy | 2090:2129 (2%)1879:1918 (2%) | view | |
| 35 | x 2 | build/VS2010/datagenbuild/VS2010/fuzzer | 25:69 (27%)25:69 (19%) | view | |
| 35 | x 2 | lib/legacylib/legacy | 1728:1767 (2%)2090:2129 (2%) | view | |
| 35 | x 2 | lib/legacylib/legacy | 2093:2132 (2%)1728:1767 (2%) | view |
Duplicated Units
The list of top 49 duplicated units.
| Size | # | Folders | Files | Lines | Code |
|---|---|---|---|---|---|
| 103 | x 3 | lib/legacylib/legacylib/legacy | 1178:1288 1179:1289 1156:1266 | view | |
| 85 | x 3 | lib/legacylib/legacylib/legacy | 2920:3019 2561:2660 2687:2786 | view | |
| 76 | x 2 | lib/legacylib/legacy | 1717:1811 1714:1808 | view | |
| 76 | x 2 | lib/legacylib/legacy | 2079:2173 2076:2170 | view | |
| 64 | x 3 | lib/legacylib/legacylib/legacy | 1542:1618 1539:1615 1692:1768 | view | |
| 54 | x 2 | lib/legacylib/legacy | 3414:3479 3056:3121 | view | |
| 53 | x 2 | lib/legacylib/legacy | 3103:3170 2744:2811 | view | |
| 52 | x 2 | lib/legacylib/legacy | 3039:3100 2680:2741 | view | |
| 45 | x 2 | lib/legacylib/legacy | 3263:3318 2904:2959 | view | |
| 44 | x 2 | lib/legacylib/legacy | 2868:2917 2509:2558 | view | |
| 43 | x 3 | lib/legacylib/legacylib/legacy | 1337:1404 1338:1405 1317:1384 | view | |
| 40 | x 3 | lib/legacylib/legacylib/legacy | 1879:1925 1876:1922 2027:2073 | view | |
| 36 | x 2 | lib/legacylib/legacy | 3335:3380 2976:3021 | view | |
| 34 | x 2 | lib/legacylib/legacy | 384:427 387:430 | view | |
| 32 | x 3 | lib/legacylib/legacylib/legacy | 1834:1875 1831:1872 1982:2023 | view | |
| 28 | x 3 | lib/legacylib/legacylib/legacy | 464:494 466:496 731:761 | view | |
| 18 | x 5 | lib/legacylib/legacylib/legacylib/legacylib/legacy | 753:772 857:876 350:369 353:372 624:643 | view | |
| 18 | x 2 | lib/legacylib/legacy | 1311:1335 1312:1336 | view | |
| 17 | x 3 | lib/legacylib/legacylib/legacy | 1420:1444 1421:1445 1403:1427 | view | |
| 17 | x 2 | lib/legacylib/legacy | 2216:2246 2363:2393 | view | |
| 16 | x 3 | lib/legacylib/legacylib/legacy | 2051:2075 2048:2072 2198:2222 | view | |
| 15 | x 2 | lib/legacylib/legacy | 203:219 362:378 | view | |
| 14 | x 3 | lib/legacylib/legacylib/legacy | 1692:1714 1689:1711 1841:1863 | view | |
| 14 | x 3 | lib/legacylib/legacylib/legacy | 2022:2037 2019:2034 2169:2184 | view | |
| 13 | x 2 | contrib/seekable_formatprograms | 88:103 86:101 | view | |
| 12 | x 4 | lib/legacylib/legacylib/legacylib/legacy | 1463:1480 2817:2834 2458:2475 2584:2601 | view | |
| 11 | x 2 | lib/legacylib/legacy | 189:201 348:360 | view | |
| 11 | x 3 | lib/legacylib/legacylib/legacy | 207:219 209:221 179:191 | view | |
| 11 | x 2 | lib/legacylib/common | 1272:1287 188:203 | view | |
| 10 | x 3 | lib/legacylib/legacylib/legacy | 594:608 1294:1308 1295:1309 | view | |
| 10 | x 3 | lib/legacylib/legacylib/legacy | 1814:1827 1811:1824 1962:1975 | view | |
| 10 | x 3 | lib/legacylib/legacylib/legacy | 2848:2863 2489:2504 2615:2630 | view | |
| 10 | x 2 | lib/legacylib/legacy | 3245:3260 2886:2901 | view | |
| 9 | x 2 | programslib/dictBuilder | 233:244 539:549 | view | |
| 9 | x 3 | lib/legacylib/legacylib/legacy | 238:248 239:249 210:220 | view | |
| 9 | x 3 | lib/legacylib/legacylib/legacy | 2176:2188 2173:2185 2320:2332 | view | |
| 8 | x 4 | lib/legacylib/legacylib/legacylib/common | 211:220 234:243 393:402 324:333 | view | |
| 8 | x 3 | lib/legacylib/legacylib/legacy | 196:205 198:207 168:177 | view | |
| 8 | x 3 | lib/legacylib/legacylib/legacy | 226:235 228:237 198:207 | view | |
| 7 | x 4 | lib/legacylib/legacylib/legacylib/common | 201:209 224:232 383:391 314:322 | view | |
| 7 | x 3 | lib/legacylib/legacylib/legacy | 3375:3383 3514:3522 3729:3737 | view | |
| 7 | x 3 | lib/legacylib/legacylib/legacy | 884:894 1407:1417 1408:1418 | view | |
| 7 | x 3 | lib/legacylib/legacylib/legacy | 544:552 2777:2785 395:403 | view | |
| 7 | x 3 | lib/legacylib/legacylib/legacy | 720:729 722:731 895:904 | view | |
| 7 | x 3 | lib/legacylib/legacylib/legacy | 731:740 733:742 906:915 | view | |
| 6 | x 2 | lib/legacylib/legacy | 3793:3800 3411:3418 | view | |
| 6 | x 4 | lib/legacylib/legacylib/legacylib/legacy | 1483:1490 2836:2843 2477:2484 2603:2610 | view | |
| 6 | x 3 | lib/legacylib/legacylib/legacy | 2063:2070 3386:3393 3028:3035 | view | |
| 6 | x 3 | lib/legacylib/legacylib/legacy | 711:718 713:720 886:893 | view |