Correct handling of ZDOTDIR variable

[yamachu]

fix: https://github.com/microsoft/vscode/issues/160889 ref: https://github.com/microsoft/vscode/issues/160920

When vscode is started from the integrated terminal, the environment variables are taken over. Therefore, the ZDOTDIR of the starting vscode is oriented to the tmp directory(os.tmpdir()). This causes a problem that the user's ZDOTDIR cannot be reflected. It also causes an infinite loop of calling .zshenv in tmpdir from .zshenv in tmpdir( This seems to be causing the zsh crashes I have reported ). Therefore, I have changed the allocation method of USER_ZDOTDIR.

This behavior was discovered by inserting the following code into the code below (between line 4 and 5) https://github.com/microsoft/vscode/blob/17bb582b8580e77ec7eaf59f980a3f7b3dfde541/src/vs/workbench/contrib/terminal/browser/media/shellIntegration-env.zsh#L4-L5

env > ~/vscode-debug/$(gdate +%s)

from iTerm2 env dump

SHLVL=2
HOME=/Users/yk-yamada
GIT_ASKPASS=/Users/yk-yamada/Projects/github.com/yamachu/vscode/extensions/git/out/askpass.sh
VSCODE_GIT_ASKPASS_NODE=/Users/yk-yamada/Projects/github.com/yamachu/vscode/.build/electron/Code - OSS.app/Contents/Frameworks/Code - OSS Helper.app/Contents/MacOS/Code - OSS Helper
VSCODE_GIT_ASKPASS_EXTRA_ARGS=
VSCODE_GIT_ASKPASS_MAIN=/Users/yk-yamada/Projects/github.com/yamachu/vscode/extensions/git/out/askpass-main.js
VSCODE_GIT_IPC_HANDLE=/var/folders/s6/yfw89gs13k78dfw2pdpj3w6h0000gp/T/vscode-git-2152275826.sock
VSCODE_INJECTION=1
ZDOTDIR=/var/folders/s6/yfw89gs13k78dfw2pdpj3w6h0000gp/T/yk-yamada-vscode-zsh
USER_ZDOTDIR=/Users/yk-yamada
_=/usr/bin/env

vscode that was run from integrated vscode zsh

SHLVL=4
HOME=/Users/yk-yamada
ZDOTDIR=/var/folders/s6/yfw89gs13k78dfw2pdpj3w6h0000gp/T/yk-yamada-vscode-zsh
USER_ZDOTDIR=/var/folders/s6/yfw89gs13k78dfw2pdpj3w6h0000gp/T/yk-yamada-vscode-zsh
GIT_ASKPASS=/Users/yk-yamada/Projects/github.com/yamachu/vscode/extensions/git/out/askpass.sh
VSCODE_GIT_ASKPASS_NODE=/Users/yk-yamada/Projects/github.com/yamachu/vscode/.build/electron/Code - OSS.app/Contents/Frameworks/Code - OSS Helper.app/Contents/MacOS/Code - OSS Helper
VSCODE_GIT_ASKPASS_EXTRA_ARGS=
VSCODE_GIT_ASKPASS_MAIN=/Users/yk-yamada/Projects/github.com/yamachu/vscode/extensions/git/out/askpass-main.js
VSCODE_GIT_IPC_HANDLE=/var/folders/s6/yfw89gs13k78dfw2pdpj3w6h0000gp/T/vscode-git-8ecc674759.sock
VSCODE_INJECTION=1
_=/usr/bin/env

with this fix

SHLVL=4
HOME=/Users/yk-yamada
ZDOTDIR=/var/folders/s6/yfw89gs13k78dfw2pdpj3w6h0000gp/T/yk-yamada-vscode-zsh
USER_ZDOTDIR=/Users/yk-yamada
GIT_ASKPASS=/Users/yk-yamada/Projects/github.com/yamachu/vscode/extensions/git/out/askpass.sh
VSCODE_GIT_ASKPASS_NODE=/Users/yk-yamada/Projects/github.com/yamachu/vscode/.build/electron/Code - OSS.app/Contents/Frameworks/Code - OSS Helper.app/Contents/MacOS/Code - OSS Helper
VSCODE_GIT_ASKPASS_EXTRA_ARGS=
VSCODE_GIT_ASKPASS_MAIN=/Users/yk-yamada/Projects/github.com/yamachu/vscode/extensions/git/out/askpass-main.js
VSCODE_GIT_IPC_HANDLE=/var/folders/s6/yfw89gs13k78dfw2pdpj3w6h0000gp/T/vscode-git-8ecc674759.sock
VSCODE_INJECTION=1
_=/usr/bin/env