minor improvements

internal/command/testdata/test/mocking/tests/plan_mocked_provider_overridden.tftest.hcl

@@ -24,6 +24,16 @@ mock_provider "test" {
   }
 }
 
+
+override_resource {
+  target = test_resource.secondary[0]
+  override_computed = true
+  values = {
+    id = "ssss"
+  }
+}
+
+
 variables {
   instances = 2
   child_instances = 1
@@ -37,4 +47,9 @@ run "test" {
     error_message = "plan should override the value when override_computed is true"
   }
 
+  assert {
+    condition = test_resource.secondary[0].id == "ssss"
+    error_message = "plan should override the value when override_computed is true"
+  }
+
 }

internal/moduletest/eval_context.go

@@ -141,7 +141,7 @@ func (ec *EvalContext) Evaluate() (Status, cty.Value, tfdiags.Diagnostics) {
 			diags = diags.Append(&hcl.Diagnostic{
 				Severity:    hcl.DiagError,
 				Summary:     "Unknown condition value",
-				Detail:      "Condition expression could not be evaluated at this time. This means you have executed a `run` block with `command = plan` and one of the values your condition depended on is not known until after the plan has been applied. Either remove this value from your condition, or execute an `apply` command from this `run` block.",
+				Detail:      "Condition expression could not be evaluated at this time. This means you have executed a `run` block with `command = plan` and one of the values your condition depended on is not known until after the plan has been applied. Either remove this value from your condition, or execute an `apply` command from this `run` block. Alternatively, if there is an override for this value, you can make it available during the plan phase by setting `override_computed = true` in the `override_` block.",
 				Subject:     rule.Condition.Range().Ptr(),
 				Expression:  rule.Condition,
 				EvalContext: hclCtx,

internal/providers/mock.go

@@ -182,8 +182,8 @@ func (m *Mock) PlanResourceChange(request PlanResourceChangeRequest) PlanResourc
 			panic(fmt.Errorf("failed to retrieve schema for resource %s", request.TypeName))
 		}
 
-		// If the provider was overriden in the test (via override_*), the mock provider is not called at all,
-		// so we can be certain that this provider is not mocked.
+		// If the provider was overriden via override_* blocks, the mock provider is not called at all,
+		// so we can continue to make computed values as unknown here (until mock defaults support plan command).
 		value, diags := mocking.PlanComputedValuesForResource(request.ProposedNewState, &mocking.MockedData{
 			ComputedAsUnknown: true,
 		}, resource.Block)