Yarn: Failure on mapIntermediaryJar

Having the same issue:

> Task :mapIntermediaryJar FAILED
:mapping minecraft to intermediary

FAILURE: Build failed with an exception.

* Where:
Build file '/home/ej/Documents/Tools/Yarn1_15/build.gradle' line: 628

* What went wrong:
Execution failed for task ':mapIntermediaryJar'.
> Failed to remap jar

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

Deprecated Gradle features were used in this build, making it incompatible with Gradle 7.0.
Use '--warning-mode all' to show the individual deprecation warnings.
See https://docs.gradle.org/6.0.1/userguide/command_line_interface.html#sec:command_line_warnings

BUILD FAILED in 23s

edit: ok, so it gets more interesting - here's the exception https://hasteb.in/yacovipu.kotlin It says the file does not exist - which is bizarre, because it definitely does?

I've seen that to

For now, guys, change the + in https://github.com/FabricMC/yarn/blob/e7852f3aa99b729af90e0f998193fb557b8f52aa/build.gradle#L15
to 0.2.1.63, like

classpath 'net.fabricmc:tiny-remapper:0.2.1.63'

tiny remapper updated asm, and apparently the old asm brought by other parts of the buildscript dislikes that.

That fix pr is merged. Pull from origin (or whatever the remote this repo is on your git local repo)'s 1.15.2 branch and build again.