chaincfg: split params into per-network files.

[JFixby]

The purpose of this PR is to reduce the number of code lines in the chaincfg/params.go (from 1262 to 650) improving its readability for future maintenance.

Changes:

• move variable MainNetParams into dedicated file mainnetparams.go
• move variable TestNetParams into dedicated file testnetparams.go
• move variable SimNetParams into dedicated file simnetparams.go

No logical changes were made. Just Cut&Paste.

[alexlyp]

nack

[davecgh]

Thanks for the PR. The change seems reasonable, however, the commit message and PR description do not conform to the Code Contribution Guidelines, most notably the Model Git Commit Messages.

Please take care of that and then I'll review the diff to ensure there are no other changes in the params.

[JFixby]

Thank you @davecgh

Should be good now.
Let me know if I still need to fix something.

[davecgh]

The commit title still exceeds the max of 50 chars. I changed the PR title to one that fits. I'll still need to review the code to ensure no changes made it in.

[davecgh]

In addition to manual review, I used the following process to ensure none of the values change:

$ git checkout master
$ cat params.go | sed -ne '/\/\/ Copyright/,/^package chaincfg/p' > mainnetparams2.go; cat params.go | sed -ne '/\/\/ MainNetParams defines the/,/^}/p' >> mainnetparams2.go
$ cat params.go | sed -ne '/\/\/ Copyright/,/^package chaincfg/p' > testnetparams2.go; cat params.go | sed -ne '/\/\/ TestNet2Params defines the/,/^}/p' >> testnetparams2.go
$ cat params.go | sed -ne '/\/\/ Copyright/,/^package chaincfg/p' > simnetparams2.go; cat params.go | sed -ne '/\/\/ SimNetParams defines the/,/^}/p' >> simnetparams2.go

$ goimports -w *params2.go

$ git checkout JFixby-brushup-chaincfg
Switched to branch 'JFixby-brushup-chaincfg'

$ openssl sha256 mainnetparams.go mainnetparams2.go
SHA256(mainnetparams.go)= 49c7d02521af618882c4972cccd39329497095ebe3dadc337e92336218a5eb41
SHA256(mainnetparams2.go)= 49c7d02521af618882c4972cccd39329497095ebe3dadc337e92336218a5eb41

$ openssl sha256 testnetparams.go testnetparams2.go
SHA256(testnetparams.go)= c364988f55d0ff424e135dac760a60bdfd99c784f9f8587a279d9d07e1e61fcd
SHA256(testnetparams2.go)= c364988f55d0ff424e135dac760a60bdfd99c784f9f8587a279d9d07e1e61fcd

$ openssl sha256 simnetparams.go simnetparams2.go
SHA256(simnetparams.go)= 4e46360de44a97dd637d58e5a198e3759346a2d62fee6b697b6ee9fa0e2a79ed
SHA256(simnetparams2.go)= 4e46360de44a97dd637d58e5a198e3759346a2d62fee6b697b6ee9fa0e2a79ed

$ rm *params2.go

[jrick]

I'm finding this change quite annoying. I was previously able to use go-to-reference in my editor to open the parameters file and then search that exact same file for the particular network's parameters I was interested in. After this change, the actual parameter values are in different files and it takes more effort to find the correct file and parameter definitions.

[JFixby]

Is it about the "Find all references"?

[jrick]

No, i'm talking about go to definition on fields of a params object, not find all references of the defined field. The latter takes exuberantly long (and it's even faster to find and open the files themselves) because the tooling has to search for any references in my entire GOPATH.

[JFixby]

Generally, it is not easy to read a file with 1262 lines of code.
Hard to read correlates with hard to maintain and hard to spot a problem.
Longer files = more bugs. Shorter files = less bugs.

As far as I understand, your case is the following:
You are somewhere in the code and you are looking for the network parameter value assignment.

I may suggest the following solution:

1. click "Jump to declaration/Go to definition" (Ctrl + mouse click)
2. select "Find all references/occurrences/usages" - there you find the assignment and that's it

However, I found that in VSCode IDE it is not that easy.

1. "Go to definition" takes 3-5 seconds, which is abnormally slow. Eclipse IDE was doing it instantly in 2005.
2. "Find all references" takes about 30-60 seconds to perform.

I checked VSCode issue tracker. Both these issues are known and were reported multiple times in there. It seems nobody is interested in fixing it. VSCode devs just keep closing the tickets.

I checked GoLanD. There I found "Find all references"-feature that does exactly what you need. It instantly returns detailed search results, that will bring you to the exact line of code you look for.

[chappjc]

I don't see those kinds of slow times. I do: - Go to definition (~1 sec). - Find in all files (CTRL-SHIFT-F, ~1sec). It's quick, but not as smooth as already having the right file opened after the first step.

…

On Wed, Jun 20, 2018, 7:13 AM J Fixby ***@***.***> wrote: Generally, it is not easy to read a file with 1262 lines of code. Hard to read correlates with hard to maintain and hard to spot a problem. Longer files = more bugs. Shorter files = less bugs. As far as I understand, your case is the following: You are somewhere in the code and you are looking for the network parameter value assignment. I may suggest the following solution: 1. click "Jump to declaration/Go to definition" (Ctrl + mouse click) 2. select "Find all references/occurrences/usages" - there you find the assignment and that's it However, I found that in VSCode IDE it is not that easy. 1. "Go to definition" takes 3-5 seconds, which is abnormally slow. Eclipse IDE was doing it instantly in 2005. 2. "Find all references" takes about 30-60 seconds to perform. I checked VSCode issue tracker. Both these issues are known and were reported multiple times in there. It seems nobody is interested in fixing it. VSCode devs just keep closing the tickets. I checked GoLanD. There I found "Find all references"-feature that does exactly what you need. It instantly returns detailed search results, that will bring you to the exact line of code you look for. [image: image] <https://user-images.githubusercontent.com/1580663/41660321-06d09642-749c-11e8-89e9-50c853cb83ac.png> — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#1265 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AI8HSdo2vh__iVoqdRGpCC1Z5LyFKf5gks5t-liRgaJpZM4UbIFF> .

[JFixby]

Good. But opening the right file in the first step is not smooth. You still have to call the CTRL-F to find the code line you need (value assignment) and scroll over 1200 lines up and down, checking you are actually looking at the right network params set, because there are 3 networks in the same file, it is easy to mix up.

Btw, GoLanD will aid you well. In one single move it will point you directly from usage code to the assignment. After this PR you just need to glance at the file name: is it the mainnetparams.go or the testnetparams.go (see screenshot above)