terraform init should pick up action providers

internal/configs/config.go

@@ -483,6 +483,15 @@ func (c *Config) addProviderRequirements(reqs providerreqs.Requirements, recurse
 		reqs[fqn] = nil
 	}
 
+	for _, rc := range c.Module.Actions {
+		fqn := rc.Provider
+		if _, exists := reqs[fqn]; exists {
+			// Explicit dependency already present
+			continue
+		}
+		reqs[fqn] = nil
+	}
+
 	// Import blocks that are generating config may have a custom provider
 	// meta-argument. Like the provider meta-argument used in resource blocks,
 	// we use this opportunity to load any implicit providers.
@@ -1022,6 +1031,9 @@ func (c *Config) EffectiveRequiredProviderConfigs() addrs.Map[addrs.RootProvider
 	for _, rc := range c.Module.DataResources {
 		maybePutLocal(rc.ProviderConfigAddr(), false)
 	}
+	for _, rc := range c.Module.Actions {
+		maybePutLocal(rc.ProviderConfigAddr(), false)
+	}
 	for _, ic := range c.Module.Import {
 		if ic.ProviderConfigRef != nil {
 			maybePutLocal(addrs.LocalProviderConfig{

internal/configs/config_test.go

@@ -29,14 +29,16 @@ func TestConfigProviderTypes(t *testing.T) {
 		t.Fatal("expected empty result from empty config")
 	}
 
-	cfg, diags := testModuleConfigFromFile("testdata/valid-files/providers-explicit-implied.tf")
+	cfg, diags := testModuleFromFileWithExperiments("testdata/valid-files/providers-explicit-implied.tf")
 	if diags.HasErrors() {
 		t.Fatal(diags.Error())
 	}
 
 	got = cfg.ProviderTypes()
+
 	want := []addrs.Provider{
 		addrs.NewDefaultProvider("aws"),
+		addrs.NewDefaultProvider("external"),
 		addrs.NewDefaultProvider("local"),
 		addrs.NewDefaultProvider("null"),
 		addrs.NewDefaultProvider("template"),

internal/configs/parser_test.go

@@ -52,6 +52,18 @@ func testModuleConfigFromFile(filename string) (*Config, hcl.Diagnostics) {
 	return cfg, append(diags, moreDiags...)
 }
 
+// testModuleFromFileWithExperiments File reads a single file from the given path as a
+// module and returns its configuration. This is a helper for use in unit tests.
+func testModuleFromFileWithExperiments(filename string) (*Config, hcl.Diagnostics) {
+	parser := NewParser(nil)
+	parser.AllowLanguageExperiments(true)
+	f, diags := parser.LoadConfigFile(filename)
+	mod, modDiags := NewModule([]*File{f}, nil)
+	diags = append(diags, modDiags...)
+	cfg, moreDiags := BuildConfig(mod, nil, nil)
+	return cfg, append(diags, moreDiags...)
+}
+
 // testModuleFromDir reads configuration from the given directory path as
 // a module and returns it. This is a helper for use in unit tests.
 func testModuleFromDir(path string) (*Module, hcl.Diagnostics) {

internal/configs/testdata/valid-files/providers-explicit-implied.tf

@@ -14,6 +14,9 @@ resource "null_resource" "foo" {
 
 }
 
+action "external_test" "foo" {
+}
+
 import {
   id = "directory/filename"
   to = local_file.foo