Earlier commits arranged for each of our tofu.Context exported methods that
perform graph-based operations to take a context.Context from their
callers, and for the main callers in package command and package backend
to connect those contexts to the top-level context from "package main"
that can potentially have an OpenTelemetry span attached to it.
This propagates those contexts a little deeper into the guts of the
language runtime, getting it as far as the shared logic that drives a
graph walk.
The next step from here would be to change the interfaces
GraphNodeExecutable and GraphNodeDynamicExpandable so that their methods
both take a context.Context, but that would involve a big sprawling
update to every implementation of each of those interfaces and so
we'll save that for a later commit to keep this one relatively clean.
This commit also reaches the first point of ambiguity where our older
conventions call for "ctx" to be the variable name for a tofu.EvalContext
rather than a context.Context. Since "ctx context.Context" is a core idiom
in the Go community, we'll switch to using evalCtx as the variable name
for tofu.EvalContext both here and in our future commits that will
modify the two main graph walk interfaces that make extensive use of the
tofu.EvalContext interface.
Signed-off-by: Martin Atkins <mart@degeneration.co.uk>
This continues our ongoing effort to get a coherent chain of
context.Context all the way from "package main" to all of our calls to
external components.
Context.Eval doesn't yet do anything with its new context, but we'll
plumb this deeper in future.
All of the _test.go file updates here are purely mechanical additions of
the extra argument. No test is materially modified by this change, which
is intentional to get some assurance that isn't a breaking change.
Signed-off-by: Martin Atkins <mart@degeneration.co.uk>
