Merge #12878: [refactor] Config handling refactoring in preparation for network-specific sections

77a733a99 [tests] Add additional unit tests for -nofoo edge cases (Anthony Towns)
af173c2be [tests] Check GetChainName works with config entries (Anthony Towns)
fa27f1c23 [tests] Add unit tests for ReadConfigStream (Anthony Towns)
087c5d204 ReadConfigStream: assume the stream is good (Anthony Towns)
6d5815aad Separate out ReadConfigStream from ReadConfigFile (Anthony Towns)
834d30341 [tests] Add unit tests for GetChainName (Anthony Towns)
11b6b5b86 Move ChainNameFromCommandLine into ArgsManager and rename to GetChainName (Anthony Towns)

Pull request description:

  This does a bit of refactoring of the configuration handling code in order to add additional tests to make adding support for [test]/[regtest] sections in the config file in #11862 easier. Should not cause any behaviour changes.

Tree-SHA512: 8d2ce1449fc180de03414e7e569d1a21ba1e9f6564e13d3faf3961f710adc725fa0d4ab49b89ebd2baa11ea36ac5018377f693a84037d386a8b8697c9d6db3e9

src/bitcoind.cpp

@@ -102,7 +102,7 @@ bool AppInit(int argc, char* argv[])
         }
         // Check for -testnet or -regtest parameter (Params() calls are only valid after this clause)
         try {
-            SelectParams(ChainNameFromCommandLine());
+            SelectParams(gArgs.GetChainName());
         } catch (const std::exception& e) {
             fprintf(stderr, "Error: %s\n", e.what());
             return false;