diff --git a/internal/command/test_test.go b/internal/command/test_test.go
index 1fe5405382..9f0e6c0130 100644
--- a/internal/command/test_test.go
+++ b/internal/command/test_test.go
@@ -267,7 +267,7 @@ func TestTest_Runs(t *testing.T) {
 		},
 		"ephemeral_input_with_error": {
 			expectedOut: []string{"Error message refers to ephemeral values", "1 passed, 1 failed."},
-			expectedErr: []string{"Test assertion failed"},
+			expectedErr: []string{"Test assertion failed", "has an ephemeral value"},
 			code:        1,
 		},
 		"ephemeral_resource": {
diff --git a/internal/moduletest/eval_context.go b/internal/moduletest/eval_context.go
index 672f1c4ee5..3822d2b119 100644
--- a/internal/moduletest/eval_context.go
+++ b/internal/moduletest/eval_context.go
@@ -179,6 +179,8 @@ func (ec *EvalContext) Evaluate() (Status, cty.Value, tfdiags.Diagnostics) {
 				Subject:     rule.Condition.Range().Ptr(),
 				Expression:  rule.Condition,
 				EvalContext: hclCtx,
+				// Make the ephemerality visible
+				Extra: terraform.DiagnosticCausedByEphemeral(true),
 			})
 			continue
 		} else {
diff --git a/internal/terraform/diagnostics.go b/internal/terraform/diagnostics.go
index 9481363ae6..ac1ff905fe 100644
--- a/internal/terraform/diagnostics.go
+++ b/internal/terraform/diagnostics.go
@@ -27,20 +27,20 @@ func (e diagnosticCausedByUnknown) DiagnosticCausedByUnknown() bool {
 	return bool(e)
 }
 
-// diagnosticCausedByEphemeral is an implementation of
+// DiagnosticCausedByEphemeral is an implementation of
 // tfdiags.DiagnosticExtraBecauseEphemeral which we can use in the "Extra" field
 // of a diagnostic to indicate that the problem was caused by ephemeral values
 // being involved in an expression evaluation.
 //
-// When using this, set the Extra to diagnosticCausedByEphemeral(true) and also
+// When using this, set the Extra to DiagnosticCausedByEphemeral(true) and also
 // populate the EvalContext and Expression fields of the diagnostic so that
 // the diagnostic renderer can use all of that information together to assist
 // the user in understanding what was ephemeral.
-type diagnosticCausedByEphemeral bool
+type DiagnosticCausedByEphemeral bool
 
-var _ tfdiags.DiagnosticExtraBecauseEphemeral = diagnosticCausedByEphemeral(true)
+var _ tfdiags.DiagnosticExtraBecauseEphemeral = DiagnosticCausedByEphemeral(true)
 
-func (e diagnosticCausedByEphemeral) DiagnosticCausedByEphemeral() bool {
+func (e DiagnosticCausedByEphemeral) DiagnosticCausedByEphemeral() bool {
 	return bool(e)
 }
 
diff --git a/internal/terraform/eval_count.go b/internal/terraform/eval_count.go
index bd86f435cb..aea7f92c17 100644
--- a/internal/terraform/eval_count.go
+++ b/internal/terraform/eval_count.go
@@ -58,7 +58,7 @@ func evaluateCountExpression(expr hcl.Expression, ctx EvalContext, allowUnknown
 			Summary:  "Invalid count argument",
 			Detail:   `The given "count" value is derived from an ephemeral value, which means that Terraform cannot persist it between plan/apply rounds. Use only non-ephemeral values here.`,
 			Subject:  expr.Range().Ptr(),
-			Extra:    diagnosticCausedByEphemeral(true),
+			Extra:    DiagnosticCausedByEphemeral(true),
 		})
 		return -1, diags
 	}
@@ -98,7 +98,7 @@ func evaluateCountExpressionValue(expr hcl.Expression, ctx EvalContext) (cty.Val
 			// we can't easily do that right now because the hcl.EvalContext
 			// (which is not the same as the ctx we have in scope here) is
 			// hidden away inside ctx.EvaluateExpr.
-			Extra: diagnosticCausedByEphemeral(true),
+			Extra: DiagnosticCausedByEphemeral(true),
 		})
 	}
 
diff --git a/internal/terraform/eval_for_each.go b/internal/terraform/eval_for_each.go
index 8742f266a6..b71cb824c5 100644
--- a/internal/terraform/eval_for_each.go
+++ b/internal/terraform/eval_for_each.go
@@ -271,7 +271,7 @@ func (ev *forEachEvaluator) ensureNotEphemeral(forEachVal cty.Value) tfdiags.Dia
 			Subject:     ev.expr.Range().Ptr(),
 			Expression:  ev.expr,
 			EvalContext: ev.hclCtx,
-			Extra:       diagnosticCausedByEphemeral(true),
+			Extra:       DiagnosticCausedByEphemeral(true),
 		})
 	}