preprocessor: support declatations in matchSpec

This allows some bash like the following:

    export BLAH=blah

to be successfully considered by a match spec.

Preprocessor-No-Write-Cache: true
Signed-off-by: Paul Jolly <[email protected]>
Change-Id: Ic9a4443159b3e4d34ea75e124f861250bf8aedd5
Dispatch-Trailer: {"type":"trybot","CL":1177001,"patchset":3,"ref":"refs/changes/01/1177001/3","targetBranch":"alpha"}

internal/cmd/preprocessor/cmd/sanitisers.go

@@ -104,34 +104,55 @@ func (m *matchSpec) matches(cmd *commandStmt) (bool, error) {
 		if !ok {
 			return false, nil
 		}
-		if m.CommandPrefix != "" {
-			if len(got.Args) < len(want.Args) {
-				return false, nil
-			}
-		} else {
-			if len(got.Args) != len(want.Args) {
-				return false, nil
-			}
+		if matched, err := matchArgs(m, got.Args, want.Args); err != nil || !matched {
+			return matched, err
 		}
-		p := syntax.NewPrinter(syntax.SingleLine(true))
-		for i := range want.Args {
-			var gotS, wantS strings.Builder
-			p.Print(&gotS, got.Args[i])
-			p.Print(&wantS, want.Args[i])
-
-			// TODO: per @mvdan, revisit whether we can/should use
-			// reflect.DeepEqual or some other mechanism here (with performance
-			// being the main consideration).
-			if gotS.String() != wantS.String() {
-				return false, nil
-			}
+	case *syntax.DeclClause:
+		want, ok := want.Cmd.(*syntax.DeclClause)
+		if !ok {
+			return false, nil
+		}
+		if got.Variant.Value != want.Variant.Value {
+			return false, nil
+		}
+		if matched, err := matchArgs(m, got.Args, want.Args); err != nil || !matched {
+			return matched, err
 		}
 	default:
 		return false, fmt.Errorf("don't know how to handle stmt of type %T", got)
 	}
 	return true, nil
 }
 
+func matchArgs[T syntax.Node](m *matchSpec, got, want []T) (bool, error) {
+	if m.CommandPrefix != "" {
+		// When in command prefix match moding, we need got to be >= want
+		if len(got) < len(want) {
+			return false, nil
+		}
+	} else {
+		// Else we need to have exactly the same length otherwise it cannot
+		// possibly be a match
+		if len(got) != len(want) {
+			return false, nil
+		}
+	}
+	p := syntax.NewPrinter(syntax.SingleLine(true))
+	for i := range want {
+		var gotS, wantS strings.Builder
+		p.Print(&gotS, got[i])
+		p.Print(&wantS, want[i])
+
+		// TODO: per @mvdan, revisit whether we can/should use
+		// reflect.DeepEqual or some other mechanism here (with performance
+		// being the main consideration).
+		if gotS.String() != wantS.String() {
+			return false, nil
+		}
+	}
+	return true, nil
+}
+
 // patternKindAndCommand defines a common type to be embedded in types that use
 // pattern-based matching.
 type patternProperties struct {

internal/cmd/preprocessor/cmd/testdata/execute_multistagescript.txtar

@@ -102,6 +102,7 @@ content: dir: page: {
 >echo hello
 >{{{end}}}
 >{{{with script "en" "cue version"}}}
+>export MYVAR=value
 >cue version
 >{{{end}}}
 >{{{with script "en" "norun"}}}
@@ -147,6 +148,7 @@ content: dir: page: {
 >echo hello
 >{{{end}}}
 >{{{with script "en" "cue version"}}}
+>export MYVAR=value
 >cue version
 >{{{end}}}
 >{{{with script "en" "norun"}}}
@@ -190,7 +192,8 @@ map: {
 $ echo hello
 hello
 ```
-```text { title="TERMINAL" codeToCopy="Y3VlIHZlcnNpb24K" }
+```text { title="TERMINAL" codeToCopy="ZXhwb3J0IE1ZVkFSPXZhbHVlCmN1ZSB2ZXJzaW9uCg==" }
+$ export MYVAR=value
 $ cue version
 cue version v0.8.0-alpha.1
 
@@ -220,7 +223,7 @@ package site
 						"in-subdir":        "J43PmA4U4WvVNMgjwuRuxRYV01FPIWNFmKMuvNPDah4="
 					}
 					multi_step: {
-						"8OE47KRJN899MV3TUJQ0JF5DR4IV4E6K09S3J26JI2QFPPH0A1EG====": [{
+						"CJTPSGKT1S5VQHE852UV8UR3GU4QGPUVRF75R4F6G64J90U51250====": [{
 							doc: """
 									# script doc comment
 									#scripttag
@@ -246,6 +249,11 @@ package site
 									hello
 
 									"""
+						}, {
+							doc:      ""
+							cmd:      "export MYVAR=value"
+							exitCode: 0
+							output:   ""
 						}, {
 							doc:      ""
 							cmd:      "cue version"