client builder: return a ClientBuildError when failing to build, instead of filtering out unexpected errors

[reivilibre]

This old method was checking invariants that were
spooky-action-at-a-distance: these invariants have changed since then,
so this would panic instead of returning a proper error to the caller.

Signed-off-by: [email protected]

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 84.26%. Comparing base (8119697) to head (2a3111a).
Report is 41 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/matrix-sdk/src/client/mod.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4016      +/-   ##
==========================================
+ Coverage   84.25%   84.26%   +0.01%     
==========================================
  Files         266      266              
  Lines       28344    28341       -3     
==========================================
+ Hits        23880    23882       +2     
+ Misses       4464     4459       -5     

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[bnjbvr]

Thanks for the PR. It's bad that you can hit this panic, I suppose it was put here as an internal-API error, and never supposed to be triggerable by users of the SDK. I think the code has evolved sufficiently that it's a bad idea for us to use assert_valid_builder_args at all: the error could also be a store error, or a discovery error, or, or, or…

So instead, I think we should:

• get rid of assert_valid_builder_args
• have Client::new return a Result<Self, ClientBuildError>.

Are you willing to make the changes here? Otherwise one of us can probably get to it at some point.

[reivilibre]

I can have a go at that soon, will have to happen after the mad rush to get this other stuff done that led to this issue.

BTW it was a SqliteStore(MissingVersion).... 🤷

i pushed onto the branch

[stefanceriu]

Makes sense to me 👍