testscript: reset verbose on new blocks (#293)

"Reset" verbose in the case that we are using ContinueOnError
so that the next block only shows verbose output in case it
is also in error. This ensures that later blocks that are not
in error, do not needlessly show verbose output because of an
earlier block that was in error.

Author: myitcv

testscript/testdata/testscript_logging.txt

@@ -72,9 +72,6 @@ FAIL: $$WORK${/}scripts${/}testscript.txt:9: unexpected command failure
 [exit status 1]
 FAIL: $$WORK${/}scripts${/}testscript.txt:9: unexpected command failure
 # comment 4 (0.000s)
-> printargs section3
-[stdout]
-["printargs" "section3"]
 # comment 5 (0.000s)
 > printargs section5
 [stdout]

testscript/testscript.go

@@ -622,6 +622,14 @@ func (ts *TestScript) run() {
 				rewind()
 				markTime()
 			}
+
+			// "Reset" verbose in the case that we are using ContinueOnError
+			// so that the next block only shows verbose output in case it
+			// is also in error. This ensures that later blocks that are not
+			// in error, do not needlessly show verbose output because of an
+			// earlier block that was in error.
+			verbose = ts.t.Verbose()
+
 			// Print phase heading and mark start of phase output.
 			fmt.Fprintf(&ts.log, "%s\n", line)
 			ts.mark = ts.log.Len()