On Mon, 2011-04-04 at 17:37 +0200, Jan Keirse wrote: > su heng <ste.suh...@gmail.com> schreef op 04/04/2011 16:31:17: > > > Hi Jan, > > > > Please kindly refer to my below comments. > > > > Regards, > > Su Heng > > > > On Mon, 2011-04-04 at 16:03 +0200, Jan Keirse wrote: > > > su heng <ste.suh...@gmail.com> schreef op 04/04/2011 15:41:38: > > > > > > > Hi, > > > > > > > > I read the SVN book, as there are three type conflicts: text, tree > and > > > > properties conflict. However, I wanna know why it is a conflict. For > > > > example, if there is a text conflict when I do merging code, I just > know > > > > there is an conflict but don't know why it is a conflict. > > > > > > > > So could u provide me some resource or hints what are the judge > rules > > > > for SVN to address it is a conflict, in this case, I can avoid more > > > > conflict when I'm coding or merging. I concert the text and tree > > > > conflict more. > > > > > > > > > > Start version is A. B and C are changes to A. > > > Change B says line 3 is 'cool!' > > > Change C says line 3 is 'boring!' > > > If you want to merge change B and C there's a conflict, because one > change > > > says the opposite of the other. > > [suheng] : thanks, However, your example just covers one condition. Can > > you give me a basic conflict rule policy of SVN so I can conclude all > > conditions? > > As your example, can I thought whenever a low revision(C) merge to a > > high revision(when B merge to A, A will be A+1), a text conflict will be > > pop up whatever the line is changed? > > In your example, the precondition is file a is revision A, then the > > same file under change B is revision B = A + n(n>0), and same file under > > change C is revision C = B + n(n>0), when change B is merged to A, we > > must commit it firstly(at this time revision A will be rise to A+n > B > > && A+n > C, then do another merge I mean change C will be merged in A+n, > > then conflict out. > > I think if C is a branch of from revision B+n(n>1) but not A, when we > > merge C+n(n>1) won't involve conflict, right? > > > > Hmm...I think it has little confusing. you can ignore my explain, just > > suggest me the basic conflict policy is appreciated.^_^ > > Ok, you misunderstood, C has nothing to do with B, it does not come after > B. As a general rule: if you changed the same line there is a conflict. > > I'll put it another way. > Imagine at some point velkswagen makes a car, and stores the information > about that car in a file, named possat.txt. > The file could have the following contents: > > --------------- > brand=vw > model=possat > tires=4 > engine=1900 > horsepower=110 > --------------- > > Now at some point VW decides there possat can be sold with another logo as > skida octevia. So they branch the file: > octevia > / > possat > > And the file becomes: > --------------- > brand=skida > model=octevia > tires=4 > engine=1900 > horsepower=110 > --------------- > > > After a few more years they decide to sell the same car under the siat > Brand: > > octevia > / > possat > \ > somesiat > > > --------------- > brand=siat > model=somesiat > tires=4 > engine=1900 > horsepower=110 > --------------- > > Now a clever engineer at siat notices that a car does not have 4 tires but > 5, in case you hit a nail along the road you get an extra one in the trunk > to get you home. So he changes tires to 5. > Now we have 3 files, possat, somesiat and octevia. They all share the same > origin, the possat is long out of production so we don't care about that > anymore, but we want the octevia fixed. > If you merge from somesiat to octevia, with the possat as mutual ancestor, > you're going to get a problem, not with the tires but with the brand and > model, because somesiat changed brand and model but octevia did as well, > who holds the truth, what brand and model should be in the octevia file? > > > Kind Regards, > > JAN KEIRSE > ICT-AFDELING • software quality & systems • software engineer > > **** DISCLAIMER **** > > http://www.tvh.com/newen2/emaildisclaimer/default.html > > "This message is delivered to all addressees subject to the conditions > set forth in the attached disclaimer, which is an integral part of this > message."
Hi Jan, I just try the example which you provided to me. Please refer to my flow: ############### step 1 submit one file possat: -------------- brand=vw model=possat tires=4 engine=1900 horsepower=110 --------------- file name:possat(possat@r159) ################ step 2 create branch octevia(possat@r160) and somesiat(possat@r161) base on file possat ################ step 3 change file possat under somesiat branch (possat@r161) -------------------- brand=siat model=somesiat tires=4 engine=1900 horsepower=110 --------------------- and submit can get (possat@r162) change file possat under octevia branch: ---------------- brand=skida model=octevia tires=4 engine=1900 horsepower=110 ---------------- and submit can get (possat@r163) ###################### step 4 change possat under trunk(possat@r161) -------------- brand=vw model=possat tires=5 engine=1900 horsepower=110 --------------- and submit can get (possat@r164) Now, I switch to branch possat or octevia, do merge from trunk. the line 'tires=5' will be merge automatically to my branch possat or octevia. Strange thing, if I switch to trunk do merge from possat or octevia, brand line and model line will be automatically overwrite trunk's lines. I'm using ecilpse + subeclipse. I will go to shell to verify the correctness. Regards, Su Heng -- QQ : 49757862 MSN: suh.ste...@hotmail.com Mobile: (0512)60780554
