Merge #157861

157861: cmd/reduce: include removed lines into output r=yuzefovich a=yuzefovich

`reduce` has several modes of operations where the "tail" queries from the reproduction are extracted to construct the special "comparison check" query. Previously, these extracted queries were omitted from the output, but now we'll include them (unreduced) at the tail.

Epic: None
Release note: None

Co-authored-by: Yahor Yuzefovich <yahor@cockroachlabs.com>

Author: craig[bot]

pkg/cmd/reduce/main.go

@@ -147,7 +147,7 @@ func reduceSQL(
 	chunkReductions int,
 	multiRegion bool,
 	tlp, costfuzz, unoptimizedOracle bool,
-) (string, error) {
+) (out string, retErr error) {
 	var settings string
 	if devLicense, ok := envutil.EnvString("COCKROACH_DEV_LICENSE", 0); ok {
 		settings += "SET CLUSTER SETTING cluster.organization = 'Cockroach Labs - Production Testing';\n"
@@ -173,6 +173,20 @@ func reduceSQL(
 
 	inputString := string(input)
 	var queryComparisonCheck string
+	// removedLines, if set, indicates the lines from the end of input that were
+	// removed from the input string (and were incorporated into
+	// queryComparisonCheck).
+	var removedLines []string
+	defer func() {
+		if retErr == nil && len(removedLines) > 0 {
+			inputTail, err := reducesql.Pretty(strings.Join(removedLines, "\n"))
+			if err != nil {
+				retErr = errors.Wrapf(err, "when pretty-printing tail")
+			} else {
+				out = out + "\n" + inputTail
+			}
+		}
+	}()
 
 	// If TLP check is requested, then we remove the last two queries from the
 	// input (each query is expected to be delimited by empty lines) which we
@@ -187,6 +201,7 @@ func reduceSQL(
 		lineIdx := len(lines) - 1
 		partitioned, lineIdx := findPreviousQuery(lines, lineIdx)
 		unpartitioned, lineIdx := findPreviousQuery(lines, lineIdx)
+		removedLines = lines[lineIdx:]
 		inputString = strings.Join(lines[:lineIdx], "\n")
 		// We make queryComparisonCheck a query that will result in an error with
 		// tlpFailureError error message when unpartitioned and partitioned queries
@@ -213,6 +228,7 @@ SELECT CASE
 		setting2, lineIdx := findPreviousQuery(lines, lineIdx)
 		setting1, lineIdx := findPreviousQuery(lines, lineIdx)
 		control, lineIdx := findPreviousQuery(lines, lineIdx)
+		removedLines = lines[lineIdx:]
 		inputString = strings.Join(lines[:lineIdx], "\n")
 		// We make queryComparisonCheck the original control / settings / perturbed
 		// statements, surrounded by sentinel statements.
@@ -247,6 +263,7 @@ SELECT '%[1]s';
 		settings2, lineIdx := findPreviousSetStatements(lines, lineIdx)
 		unoptimized, lineIdx := findPreviousQuery(lines, lineIdx)
 		settings1, lineIdx := findPreviousSetStatements(lines, lineIdx)
+		removedLines = lines[lineIdx:]
 		inputString = strings.Join(lines[:lineIdx], "\n")
 		// We make queryComparisonCheck the original unoptimized / settings /
 		// optimized statements, surrounded by sentinel statements.
@@ -372,7 +389,7 @@ SELECT '%[1]s';
 		return containsRE.Match(out), logOriginalHint
 	}
 
-	out, err := reduce.Reduce(
+	return reduce.Reduce(
 		logger,
 		inputSQL,
 		isInteresting,
@@ -381,7 +398,6 @@ SELECT '%[1]s';
 		chunkReducer,
 		reducesql.SQLPasses...,
 	)
-	return out, err
 }
 
 // findPreviousQuery return the query preceding lineIdx without a semicolon.