terraform test: check specific dependencies before skipping run blocks

Author: Liam Cervante

internal/command/test_test.go

@@ -339,6 +339,11 @@ func TestTest_Runs(t *testing.T) {
 			expectedOut: []string{"1 passed, 0 failed."},
 			code:        0,
 		},
+		"parallel-errors": {
+			expectedOut: []string{"1 passed, 1 failed, 1 skipped."},
+			expectedErr: []string{"Invalid condition run"},
+			code:        1,
+		},
 	}
 	for name, tc := range tcs {
 		t.Run(name, func(t *testing.T) {

internal/command/testdata/test/parallel-errors/main.tf

@@ -0,0 +1,11 @@
+variable "input" {
+  type = string
+}
+
+resource "test_resource" "foo" {
+  value = var.input
+}
+
+output "value" {
+  value = test_resource.foo.value
+}

internal/command/testdata/test/parallel-errors/main.tftest.hcl

@@ -0,0 +1,32 @@
+test {
+  parallel = true
+}
+
+run "one" {
+  state_key = "one"
+
+  variables {
+    input = "one"
+  }
+
+  assert {
+    condition = output.value
+    error_message = "something"
+  }
+}
+
+run "two" {
+  state_key = "two"
+
+  variables {
+    input = run.one.value
+  }
+}
+
+run "three" {
+  state_key = "three"
+
+  variables {
+    input = "three"
+  }
+}

internal/moduletest/graph/apply.go

@@ -104,10 +104,7 @@ func (n *NodeTestRun) testApply(ctx *EvalContext, variables terraform.InputValue
 	newStatus, outputVals, moreDiags := ctx.EvaluateRun(run, applyScope, testOnlyVariables)
 	run.Status = newStatus
 	run.Diagnostics = run.Diagnostics.Append(moreDiags)
-
-	// Now we've successfully validated this run block, lets add it into
-	// our prior run outputs so future run blocks can access it.
-	ctx.SetOutput(run, outputVals)
+	run.Outputs = outputVals
 
 	// Only update the most recent run and state if the state was
 	// actually updated by this change. We want to use the run that

internal/moduletest/graph/eval_context.go

@@ -7,7 +7,6 @@ import (
 	"context"
 	"fmt"
 	"log"
-	"maps"
 	"sort"
 	"sync"
 
@@ -44,14 +43,8 @@ type TestFileState struct {
 type EvalContext struct {
 	VariableCache *hcltest.VariableCache
 
-	// runOutputs is a mapping from run addresses to cty object values
-	// representing the collected output values from the module under test.
-	//
-	// This is used to allow run blocks to refer back to the output values of
-	// previous run blocks. It is passed into the Evaluate functions that
-	// validate the test assertions, and used when calculating values for
-	// variables within run blocks.
-	runOutputs  map[addrs.Run]cty.Value
+	// runBlocks caches all the known run blocks that this EvalContext manages.
+	runBlocks   map[addrs.Run]*moduletest.Run
 	outputsLock sync.Mutex
 
 	// configProviders is a cache of config keys mapped to all the providers
@@ -99,7 +92,7 @@ func NewEvalContext(opts EvalContextOpts) *EvalContext {
 	cancelCtx, cancel := context.WithCancel(opts.CancelCtx)
 	stopCtx, stop := context.WithCancel(opts.StopCtx)
 	return &EvalContext{
-		runOutputs:      make(map[addrs.Run]cty.Value),
+		runBlocks:       make(map[addrs.Run]*moduletest.Run),
 		outputsLock:     sync.Mutex{},
 		configProviders: make(map[string]map[string]bool),
 		providersLock:   sync.Mutex{},
@@ -313,17 +306,28 @@ func (ec *EvalContext) EvaluateRun(run *moduletest.Run, resultScope *lang.Scope,
 	return status, cty.ObjectVal(outputVals), diags
 }
 
-func (ec *EvalContext) SetOutput(run *moduletest.Run, output cty.Value) {
+func (ec *EvalContext) AddRunBlock(run *moduletest.Run) {
 	ec.outputsLock.Lock()
 	defer ec.outputsLock.Unlock()
-	ec.runOutputs[run.Addr()] = output
+	ec.runBlocks[run.Addr()] = run
 }
 
 func (ec *EvalContext) GetOutputs() map[addrs.Run]cty.Value {
 	ec.outputsLock.Lock()
 	defer ec.outputsLock.Unlock()
-	outputCopy := make(map[addrs.Run]cty.Value, len(ec.runOutputs))
-	maps.Copy(outputCopy, ec.runOutputs) // don't use clone here, so we can return a non-nil map
+	outputCopy := make(map[addrs.Run]cty.Value, len(ec.runBlocks))
+	for addr, run := range ec.runBlocks {
+		// Normally, we should check the run.Status before reading the outputs
+		// to make sure they are actually valid. But, for now we are tracking
+		// a difference between run blocks not yet executed and run blocks that
+		// do not exist by setting cty.NilVal for run blocks that haven't
+		// executed yet so we do actually just want to include all run blocks
+		// here.
+		// TODO(liamcervante): Validate run status before adding to this map
+		// once providers and variables are in the graph and we don't need to
+		// rely on this hack.
+		outputCopy[addr] = run.Outputs
+	}
 	return outputCopy
 }
 
@@ -378,6 +382,60 @@ func (ec *EvalContext) GetFileState(key string) *TestFileState {
 	return ec.FileStates[key]
 }
 
+// ReferencesCompleted returns true if all the listed references were actually
+// executed successfully. This allows nodes in the graph to decide if they
+// should execute or not based on the
+//
+// TODO(liamcervante): Expand this with providers and variables once we've added
+// them to the graph.
+func (ec *EvalContext) ReferencesCompleted(refs []*addrs.Reference) bool {
+	for _, ref := range refs {
+		switch ref := ref.Subject.(type) {
+		case addrs.Run:
+			ec.outputsLock.Lock()
+			if run, ok := ec.runBlocks[ref]; ok {
+				if run.Status != moduletest.Pass && run.Status != moduletest.Fail {
+					ec.outputsLock.Unlock()
+
+					// see also prior runs completed
+
+					return false
+				}
+			}
+			ec.outputsLock.Unlock()
+		}
+	}
+	return true
+}
+
+// PriorRunsCompleted checks a list of run blocks against our internal log of
+// completed run blocks and makes sure that any that do exist successfully
+// executed to completion.
+//
+// Note that run blocks that are not in the list indicate a bad reference,
+// which we ignore here. This is actually the problem of the caller to identify
+// and error.
+func (ec *EvalContext) PriorRunsCompleted(runs map[addrs.Run]*moduletest.Run) bool {
+	ec.outputsLock.Lock()
+	defer ec.outputsLock.Unlock()
+
+	for addr := range runs {
+		if run, ok := ec.runBlocks[addr]; ok {
+			if run.Status != moduletest.Pass && run.Status != moduletest.Fail {
+
+				// pass and fail indicate the run block still executed the plan
+				// or apply operate and wrote outputs. fail means the
+				// post-execution checks failed, but we still had data to check.
+				// this is in contrast to pending, skip, or error which indicate
+				// that we never even wrote data for this run block.
+
+				return false
+			}
+		}
+	}
+	return true
+}
+
 // evaluationData augments an underlying lang.Data -- presumably resulting
 // from a terraform.Context.PlanAndEval or terraform.Context.ApplyAndEval call --
 // with results from prior runs that should therefore be available when

internal/moduletest/graph/eval_context_test.go

@@ -730,16 +730,21 @@ func TestEvalContext_Evaluate(t *testing.T) {
 				ModuleConfig: config,
 			}
 
-			priorOutputs := make(map[addrs.Run]cty.Value, len(test.priorOutputs))
-			for name, val := range test.priorOutputs {
-				priorOutputs[addrs.Run{Name: name}] = val
-			}
-
 			testCtx := NewEvalContext(EvalContextOpts{
 				CancelCtx: context.Background(),
 				StopCtx:   context.Background(),
 			})
-			testCtx.runOutputs = priorOutputs
+			testCtx.runBlocks = make(map[addrs.Run]*moduletest.Run)
+			for ix, block := range file.Runs[:len(file.Runs)-1] {
+
+				// all prior run blocks we just mark as having passed, and with
+				// the output data specified by the test
+
+				run := moduletest.NewRun(block, config, ix)
+				run.Status = moduletest.Pass
+				run.Outputs = test.priorOutputs[run.Name]
+				testCtx.runBlocks[run.Addr()] = run
+			}
 			gotStatus, gotOutputs, diags := testCtx.EvaluateRun(run, planScope, test.testOnlyVars)
 
 			if got, want := gotStatus, test.expectedStatus; got != want {

internal/moduletest/graph/node_test_run.go

@@ -23,8 +23,9 @@ var (
 )
 
 type NodeTestRun struct {
-	run  *moduletest.Run
-	opts *graphOptions
+	run       *moduletest.Run
+	priorRuns map[addrs.Run]*moduletest.Run
+	opts      *graphOptions
 }
 
 func (n *NodeTestRun) Run() *moduletest.Run {
@@ -62,10 +63,9 @@ func (n *NodeTestRun) Execute(evalCtx *EvalContext) {
 		file.UpdateStatus(run.Status)
 	}()
 
-	if file.GetStatus() == moduletest.Error {
-		// If the overall test file has errored, we don't keep trying to
-		// execute tests. Instead, we mark all remaining run blocks as
-		// skipped, print the status, and move on.
+	if !evalCtx.PriorRunsCompleted(n.priorRuns) || !evalCtx.ReferencesCompleted(n.References()) {
+		// If any of our prior runs or references weren't completed successfully
+		// then we will just skip this run block.
 		run.Status = moduletest.Skip
 		return
 	}

internal/moduletest/graph/plan.go

@@ -72,10 +72,7 @@ func (n *NodeTestRun) testPlan(ctx *EvalContext, variables terraform.InputValues
 	newStatus, outputVals, moreDiags := ctx.EvaluateRun(run, planScope, testOnlyVariables)
 	run.Status = newStatus
 	run.Diagnostics = run.Diagnostics.Append(moreDiags)
-
-	// Now we've successfully validated this run block, lets add it into
-	// our prior run outputs so future run blocks can access it.
-	ctx.SetOutput(run, outputVals)
+	run.Outputs = outputVals
 }
 
 func (n *NodeTestRun) plan(ctx *EvalContext, tfCtx *terraform.Context, variables terraform.InputValues, waiter *operationWaiter) (*lang.Scope, *plans.Plan, tfdiags.Diagnostics) {

internal/moduletest/graph/transform_context.go

@@ -4,8 +4,6 @@
 package graph
 
 import (
-	"github.com/zclconf/go-cty/cty"
-
 	"github.com/hashicorp/terraform/internal/dag"
 	"github.com/hashicorp/terraform/internal/moduletest"
 	"github.com/hashicorp/terraform/internal/states"
@@ -31,7 +29,7 @@ func (e *EvalContextTransformer) Transform(graph *terraform.Graph) error {
 				// TODO(liamcervante): Once providers are embedded in the graph
 				// we don't need to track run blocks in this way anymore.
 
-				ctx.SetOutput(run, cty.NilVal)
+				ctx.AddRunBlock(run)
 
 				// We also want to set an empty state file for every state key
 				// we're going to be executing within the graph.

internal/moduletest/graph/transform_test_run.go

@@ -4,7 +4,9 @@
 package graph
 
 import (
+	"github.com/hashicorp/terraform/internal/addrs"
 	"github.com/hashicorp/terraform/internal/dag"
+	"github.com/hashicorp/terraform/internal/moduletest"
 	"github.com/hashicorp/terraform/internal/terraform"
 )
 
@@ -18,7 +20,7 @@ func (t *TestRunTransformer) Transform(g *terraform.Graph) error {
 	// Create and add nodes for each run
 	var nodes []*NodeTestRun
 	for _, run := range t.opts.File.Runs {
-		node := &NodeTestRun{run: run, opts: t.opts}
+		node := &NodeTestRun{run: run, opts: t.opts, priorRuns: make(map[addrs.Run]*moduletest.Run)}
 		g.Add(node)
 		nodes = append(nodes, node)
 	}
@@ -49,6 +51,7 @@ func (t *TestRunTransformer) controlParallelism(g *terraform.Graph, nodes []*Nod
 		// Connect to all previous runs
 		for j := 0; j < i; j++ {
 			g.Connect(dag.BasicEdge(node, nodes[j]))
+			node.priorRuns[nodes[j].run.Addr()] = nodes[j].run
 		}
 
 		// Connect to all subsequent runs
@@ -66,6 +69,7 @@ func (t *TestRunTransformer) connectSameStateRuns(g *terraform.Graph, nodes []*N
 	}
 	for _, runs := range stateRuns {
 		for i := 1; i < len(runs); i++ {
+			runs[i].priorRuns[runs[i-1].run.Addr()] = runs[i-1].run
 			g.Connect(dag.BasicEdge(runs[i], runs[i-1]))
 		}
 	}