testing: fix many test2json inaccuracies

Test2json is parsing the output stream from the test, which includes
package testing's own framing lines intermingled with other output,
in particular any output printed via fmt.Printf, println, and so on.
We have had recurring problems with unexpected partial output lines
causing a framing line to be missed.

A recent talk at GopherCon gave an example of an integration test
involving Docker that happened to print \r-terminated lines instead
of \n-terminated lines in some configurations, which in turn broke
test2json badly. (https://www.gophercon.com/agenda/session/944259)

There are also a variety of open reported issues with similar problems,
which this CL also addresses. The general approach is to add a new
testing flag -test.v=json that means to print additional output to help
test2json. And then test2json takes advantage of that output.

Among the fixes:

 - Identify testing framing more reliably, using ^V
   (#23036, #26325, #43683, GopherCon talk)
 - Test that output with \r\n endings is handled correctly
   (#43683, #34286)
 - Use === RUN in fuzz tests (#52636, #48132)
 - Add === RUN lines to note benchmark starts (#27764, #49505)
 - Print subtest --- PASS/FAIL lines as they happen (#29811)
 - Add === NAME lines to emit more test change events,
   such as when a subtest stops and the parent continues running.
 - Fix event shown in overall test failure (#27568)
 - Avoid interleaving of writes to os.Stdout and os.Stderr (#33419)

Fixes #23036.
Fixes #26325.
Fixes #27568.
Fixes #27764.
Fixes #29811.
Fixes #33419.
Fixes #34286.
Fixes #43683.
Fixes #49505.
Fixes #52636.

Change-Id: Id4207b746a20693f92e52d68c6e4a7f8c41cc7c6
Reviewed-on: https://go-review.googlesource.com/c/go/+/443596
Auto-Submit: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

8 files changed, 456 insertions, 0 deletions

diff --git a/src/cmd/internal/test2json/testdata/frame.json b/src/cmd/internal/test2json/testdata/frame.json
new file mode 100644
index 0000000000..d2a65fc36b
--- /dev/null
+++ b/src/cmd/internal/test2json/testdata/frame.json
@@ -0,0 +1,9 @@
+{"Action":"run","Test":"TestAscii"}
+{"Action":"output","Test":"TestAscii","Output":"=== RUN   TestAscii\n"}
+{"Action":"output","Test":"TestAscii","Output":"=== RUN   TestNotReally\n"}
+{"Action":"output","Test":"TestAscii","Output":"--- PASS: TestAscii\n"}
+{"Action":"output","Test":"TestAscii","Output":"    i can eat glass, and it doesn't hurt me. i can eat glass, and it doesn't hurt me.\n"}
+{"Action":"output","Test":"TestAscii","Output":"FAIL\n"}
+{"Action":"pass","Test":"TestAscii"}
+{"Action":"output","Output":"PASS\n"}
+{"Action":"pass"}
diff --git a/src/cmd/internal/test2json/testdata/frame.test b/src/cmd/internal/test2json/testdata/frame.test
new file mode 100644
index 0000000000..ec7d453027
--- /dev/null
+++ b/src/cmd/internal/test2json/testdata/frame.test
@@ -0,0 +1,6 @@
+=== RUN   TestAscii
+=== RUN   TestNotReally
+--- PASS: TestAscii
+    i can eat glass, and it doesn't hurt me. i can eat glass, and it doesn't hurt me.
+FAIL
+PASS
diff --git a/src/cmd/internal/test2json/testdata/framebig.json b/src/cmd/internal/test2json/testdata/framebig.json
new file mode 100644
index 0000000000..ebb9bdf3f1
--- /dev/null
+++ b/src/cmd/internal/test2json/testdata/framebig.json
@@ -0,0 +1,167 @@
+{"Action":"run","Test":"TestIndex"}
+{"Action":"output","Test":"TestIndex","Output":"=== RUN   TestIndex\n"}
+{"Action":"output","Test":"TestIndex","Output":"--- PASS: TestIndex (0.00s)\n"}
+{"Action":"pass","Test":"TestIndex"}
+{"Action":"pass","Test":"TestIndex"}
+{"Action":"output","Test":"TestIndex","Output":"=== PASS  TestIndex\n"}
+{"Action":"run","Test":"TestLastIndex"}
+{"Action":"output","Test":"TestLastIndex","Output":"=== RUN   TestLastIndex\n"}
+{"Action":"output","Test":"TestLastIndex","Output":"--- PASS: TestLastIndex (0.00s)\n"}
+{"Action":"pass","Test":"TestLastIndex"}
+{"Action":"pass","Test":"TestLastIndex"}
+{"Action":"output","Test":"TestLastIndex","Output":"=== PASS  TestLastIndex\n"}
+{"Action":"run","Test":"TestIndexAny"}
+{"Action":"output","Test":"TestIndexAny","Output":"=== RUN   TestIndexAny\n"}
+{"Action":"output","Test":"TestIndexAny","Output":"--- PASS: TestIndexAny (0.00s)\n"}
+{"Action":"pass","Test":"TestIndexAny"}
+{"Action":"pass","Test":"TestIndexAny"}
+{"Action":"output","Test":"TestIndexAny","Output":"=== PASS  TestIndexAny\n"}
+{"Action":"run","Test":"TestLastIndexAny"}
+{"Action":"output","Test":"TestLastIndexAny","Output":"=== RUN   TestLastIndexAny\n"}
+{"Action":"output","Test":"TestLastIndexAny","Output":"--- PASS: TestLastIndexAny (0.00s)\n"}
+{"Action":"pass","Test":"TestLastIndexAny"}
+{"Action":"pass","Test":"TestLastIndexAny"}
+{"Action":"output","Test":"TestLastIndexAny","Output":"=== PASS  TestLastIndexAny\n"}
+{"Action":"run","Test":"TestIndexByte"}
+{"Action":"output","Test":"TestIndexByte","Output":"=== RUN   TestIndexByte\n"}
+{"Action":"output","Test":"TestIndexByte","Output":"--- PASS: TestIndexByte (0.00s)\n"}
+{"Action":"pass","Test":"TestIndexByte"}
+{"Action":"pass","Test":"TestIndexByte"}
+{"Action":"output","Test":"TestIndexByte","Output":"=== PASS  TestIndexByte\n"}
+{"Action":"run","Test":"TestLastIndexByte"}
+{"Action":"output","Test":"TestLastIndexByte","Output":"=== RUN   TestLastIndexByte\n"}
+{"Action":"output","Test":"TestLastIndexByte","Output":"--- PASS: TestLastIndexByte (0.00s)\n"}
+{"Action":"pass","Test":"TestLastIndexByte"}
+{"Action":"pass","Test":"TestLastIndexByte"}
+{"Action":"output","Test":"TestLastIndexByte","Output":"=== PASS  TestLastIndexByte\n"}
+{"Action":"run","Test":"TestIndexRandom"}
+{"Action":"output","Test":"TestIndexRandom","Output":"=== RUN   TestIndexRandom\n"}
+{"Action":"output","Test":"TestIndexRandom","Output":"--- PASS: TestIndexRandom (0.00s)\n"}
+{"Action":"pass","Test":"TestIndexRandom"}
+{"Action":"pass","Test":"TestIndexRandom"}
+{"Action":"output","Test":"TestIndexRandom","Output":"=== PASS  TestIndexRandom\n"}
+{"Action":"run","Test":"TestIndexRune"}
+{"Action":"output","Test":"TestIndexRune","Output":"=== RUN   TestIndexRune\n"}
+{"Action":"output","Test":"TestIndexRune","Output":"--- PASS: TestIndexRune (0.00s)\n"}
+{"Action":"pass","Test":"TestIndexRune"}
+{"Action":"pass","Test":"TestIndexRune"}
+{"Action":"output","Test":"TestIndexRune","Output":"=== PASS  TestIndexRune\n"}
+{"Action":"run","Test":"TestIndexFunc"}
+{"Action":"output","Test":"TestIndexFunc","Output":"=== RUN   TestIndexFunc\n"}
+{"Action":"output","Test":"TestIndexFunc","Output":"--- PASS: TestIndexFunc (0.00s)\n"}
+{"Action":"pass","Test":"TestIndexFunc"}
+{"Action":"pass","Test":"TestIndexFunc"}
+{"Action":"output","Test":"TestIndexFunc","Output":"=== PASS  TestIndexFunc\n"}
+{"Action":"run","Test":"ExampleIndex"}
+{"Action":"output","Test":"ExampleIndex","Output":"=== RUN   ExampleIndex\n"}
+{"Action":"output","Test":"ExampleIndex","Output":"--- PASS: ExampleIndex (0.00s)\n"}
+{"Action":"pass","Test":"ExampleIndex"}
+{"Action":"run","Test":"ExampleIndexFunc"}
+{"Action":"output","Test":"ExampleIndexFunc","Output":"=== RUN   ExampleIndexFunc\n"}
+{"Action":"output","Test":"ExampleIndexFunc","Output":"--- PASS: ExampleIndexFunc (0.00s)\n"}
+{"Action":"pass","Test":"ExampleIndexFunc"}
+{"Action":"run","Test":"ExampleIndexAny"}
+{"Action":"output","Test":"ExampleIndexAny","Output":"=== RUN   ExampleIndexAny\n"}
+{"Action":"output","Test":"ExampleIndexAny","Output":"--- PASS: ExampleIndexAny (0.00s)\n"}
+{"Action":"pass","Test":"ExampleIndexAny"}
+{"Action":"run","Test":"ExampleIndexByte"}
+{"Action":"output","Test":"ExampleIndexByte","Output":"=== RUN   ExampleIndexByte\n"}
+{"Action":"output","Test":"ExampleIndexByte","Output":"--- PASS: ExampleIndexByte (0.00s)\n"}
+{"Action":"pass","Test":"ExampleIndexByte"}
+{"Action":"run","Test":"ExampleIndexRune"}
+{"Action":"output","Test":"ExampleIndexRune","Output":"=== RUN   ExampleIndexRune\n"}
+{"Action":"output","Test":"ExampleIndexRune","Output":"--- PASS: ExampleIndexRune (0.00s)\n"}
+{"Action":"pass","Test":"ExampleIndexRune"}
+{"Action":"run","Test":"ExampleLastIndex"}
+{"Action":"output","Test":"ExampleLastIndex","Output":"=== RUN   ExampleLastIndex\n"}
+{"Action":"output","Test":"ExampleLastIndex","Output":"--- PASS: ExampleLastIndex (0.00s)\n"}
+{"Action":"pass","Test":"ExampleLastIndex"}
+{"Action":"run","Test":"ExampleLastIndexAny"}
+{"Action":"output","Test":"ExampleLastIndexAny","Output":"=== RUN   ExampleLastIndexAny\n"}
+{"Action":"output","Test":"ExampleLastIndexAny","Output":"--- PASS: ExampleLastIndexAny (0.00s)\n"}
+{"Action":"pass","Test":"ExampleLastIndexAny"}
+{"Action":"run","Test":"ExampleLastIndexByte"}
+{"Action":"output","Test":"ExampleLastIndexByte","Output":"=== RUN   ExampleLastIndexByte\n"}
+{"Action":"output","Test":"ExampleLastIndexByte","Output":"--- PASS: ExampleLastIndexByte (0.00s)\n"}
+{"Action":"pass","Test":"ExampleLastIndexByte"}
+{"Action":"run","Test":"ExampleLastIndexFunc"}
+{"Action":"output","Test":"ExampleLastIndexFunc","Output":"=== RUN   ExampleLastIndexFunc\n"}
+{"Action":"output","Test":"ExampleLastIndexFunc","Output":"--- PASS: ExampleLastIndexFunc (0.00s)\n"}
+{"Action":"pass","Test":"ExampleLastIndexFunc"}
+{"Action":"output","Output":"goos: darwin\n"}
+{"Action":"output","Output":"goarch: amd64\n"}
+{"Action":"output","Output":"pkg: strings\n"}
+{"Action":"output","Output":"cpu: Intel(R) Core(TM) i9-9980HK CPU @ 2.40GHz\n"}
+{"Action":"run","Test":"BenchmarkIndexRune"}
+{"Action":"output","Test":"BenchmarkIndexRune","Output":"=== RUN   BenchmarkIndexRune\n"}
+{"Action":"output","Test":"BenchmarkIndexRune","Output":"BenchmarkIndexRune\n"}
+{"Action":"output","Test":"BenchmarkIndexRune","Output":"BenchmarkIndexRune-16              \t87335496\t        14.27 ns/op\n"}
+{"Action":"run","Test":"BenchmarkIndexRuneLongString"}
+{"Action":"output","Test":"BenchmarkIndexRuneLongString","Output":"=== RUN   BenchmarkIndexRuneLongString\n"}
+{"Action":"output","Test":"BenchmarkIndexRuneLongString","Output":"BenchmarkIndexRuneLongString\n"}
+{"Action":"output","Test":"BenchmarkIndexRuneLongString","Output":"BenchmarkIndexRuneLongString-16    \t57104472\t        18.66 ns/op\n"}
+{"Action":"run","Test":"BenchmarkIndexRuneFastPath"}
+{"Action":"output","Test":"BenchmarkIndexRuneFastPath","Output":"=== RUN   BenchmarkIndexRuneFastPath\n"}
+{"Action":"output","Test":"BenchmarkIndexRuneFastPath","Output":"BenchmarkIndexRuneFastPath\n"}
+{"Action":"output","Test":"BenchmarkIndexRuneFastPath","Output":"BenchmarkIndexRuneFastPath-16      \t262380160\t         4.499 ns/op\n"}
+{"Action":"run","Test":"BenchmarkIndex"}
+{"Action":"output","Test":"BenchmarkIndex","Output":"=== RUN   BenchmarkIndex\n"}
+{"Action":"output","Test":"BenchmarkIndex","Output":"BenchmarkIndex\n"}
+{"Action":"output","Test":"BenchmarkIndex","Output":"BenchmarkIndex-16                  \t248529364\t         4.697 ns/op\n"}
+{"Action":"run","Test":"BenchmarkLastIndex"}
+{"Action":"output","Test":"BenchmarkLastIndex","Output":"=== RUN   BenchmarkLastIndex\n"}
+{"Action":"output","Test":"BenchmarkLastIndex","Output":"BenchmarkLastIndex\n"}
+{"Action":"output","Test":"BenchmarkLastIndex","Output":"BenchmarkLastIndex-16              \t293688756\t         4.166 ns/op\n"}
+{"Action":"run","Test":"BenchmarkIndexByte"}
+{"Action":"output","Test":"BenchmarkIndexByte","Output":"=== RUN   BenchmarkIndexByte\n"}
+{"Action":"output","Test":"BenchmarkIndexByte","Output":"BenchmarkIndexByte\n"}
+{"Action":"output","Test":"BenchmarkIndexByte","Output":"BenchmarkIndexByte-16              \t310338391\t         3.608 ns/op\n"}
+{"Action":"run","Test":"BenchmarkIndexHard1"}
+{"Action":"output","Test":"BenchmarkIndexHard1","Output":"=== RUN   BenchmarkIndexHard1\n"}
+{"Action":"output","Test":"BenchmarkIndexHard1","Output":"BenchmarkIndexHard1\n"}
+{"Action":"output","Test":"BenchmarkIndexHard1","Output":"BenchmarkIndexHard1-16             \t   12852\t     92380 ns/op\n"}
+{"Action":"run","Test":"BenchmarkIndexHard2"}
+{"Action":"output","Test":"BenchmarkIndexHard2","Output":"=== RUN   BenchmarkIndexHard2\n"}
+{"Action":"output","Test":"BenchmarkIndexHard2","Output":"BenchmarkIndexHard2\n"}
+{"Action":"output","Test":"BenchmarkIndexHard2","Output":"BenchmarkIndexHard2-16             \t    8977\t    135080 ns/op\n"}
+{"Action":"run","Test":"BenchmarkIndexHard3"}
+{"Action":"output","Test":"BenchmarkIndexHard3","Output":"=== RUN   BenchmarkIndexHard3\n"}
+{"Action":"output","Test":"BenchmarkIndexHard3","Output":"BenchmarkIndexHard3\n"}
+{"Action":"output","Test":"BenchmarkIndexHard3","Output":"BenchmarkIndexHard3-16             \t    1885\t    532079 ns/op\n"}
+{"Action":"run","Test":"BenchmarkIndexHard4"}
+{"Action":"output","Test":"BenchmarkIndexHard4","Output":"=== RUN   BenchmarkIndexHard4\n"}
+{"Action":"output","Test":"BenchmarkIndexHard4","Output":"BenchmarkIndexHard4\n"}
+{"Action":"output","Test":"BenchmarkIndexHard4","Output":"BenchmarkIndexHard4-16             \t    2298\t    533435 ns/op\n"}
+{"Action":"run","Test":"BenchmarkLastIndexHard1"}
+{"Action":"output","Test":"BenchmarkLastIndexHard1","Output":"=== RUN   BenchmarkLastIndexHard1\n"}
+{"Action":"output","Test":"BenchmarkLastIndexHard1","Output":"BenchmarkLastIndexHard1\n"}
+{"Action":"output","Test":"BenchmarkLastIndexHard1","Output":"BenchmarkLastIndexHard1-16         \t     813\t   1295767 ns/op\n"}
+{"Action":"run","Test":"BenchmarkLastIndexHard2"}
+{"Action":"output","Test":"BenchmarkLastIndexHard2","Output":"=== RUN   BenchmarkLastIndexHard2\n"}
+{"Action":"output","Test":"BenchmarkLastIndexHard2","Output":"BenchmarkLastIndexHard2\n"}
+{"Action":"output","Test":"BenchmarkLastIndexHard2","Output":"BenchmarkLastIndexHard2-16         \t     784\t   1389403 ns/op\n"}
+{"Action":"run","Test":"BenchmarkLastIndexHard3"}
+{"Action":"output","Test":"BenchmarkLastIndexHard3","Output":"=== RUN   BenchmarkLastIndexHard3\n"}
+{"Action":"output","Test":"BenchmarkLastIndexHard3","Output":"BenchmarkLastIndexHard3\n"}
+{"Action":"output","Test":"BenchmarkLastIndexHard3","Output":"BenchmarkLastIndexHard3-16         \t     913\t   1316608 ns/op\n"}
+{"Action":"run","Test":"BenchmarkIndexTorture"}
+{"Action":"output","Test":"BenchmarkIndexTorture","Output":"=== RUN   BenchmarkIndexTorture\n"}
+{"Action":"output","Test":"BenchmarkIndexTorture","Output":"BenchmarkIndexTorture\n"}
+{"Action":"output","Test":"BenchmarkIndexTorture","Output":"BenchmarkIndexTorture-16           \t   98090\t     10201 ns/op\n"}
+{"Action":"run","Test":"BenchmarkIndexAnyASCII"}
+{"Action":"output","Test":"BenchmarkIndexAnyASCII","Output":"=== RUN   BenchmarkIndexAnyASCII\n"}
+{"Action":"output","Test":"BenchmarkIndexAnyASCII","Output":"BenchmarkIndexAnyASCII\n"}
+{"Action":"run","Test":"BenchmarkIndexAnyASCII/1:1"}
+{"Action":"output","Test":"BenchmarkIndexAnyASCII/1:1","Output":"=== RUN   BenchmarkIndexAnyASCII/1:1\n"}
+{"Action":"output","Test":"BenchmarkIndexAnyASCII/1:1","Output":"BenchmarkIndexAnyASCII/1:1\n"}
+{"Action":"output","Test":"BenchmarkIndexAnyASCII/1:1","Output":"BenchmarkIndexAnyASCII/1:1-16      \t214829462\t         5.592 ns/op\n"}
+{"Action":"run","Test":"BenchmarkIndexAnyASCII/1:2"}
+{"Action":"output","Test":"BenchmarkIndexAnyASCII/1:2","Output":"=== RUN   BenchmarkIndexAnyASCII/1:2\n"}
+{"Action":"output","Test":"BenchmarkIndexAnyASCII/1:2","Output":"BenchmarkIndexAnyASCII/1:2\n"}
+{"Action":"output","Test":"BenchmarkIndexAnyASCII/1:2","Output":"BenchmarkIndexAnyASCII/1:2-16      \t155499682\t         7.214 ns/op\n"}
+{"Action":"run","Test":"BenchmarkIndexAnyASCII/1:4"}
+{"Action":"output","Test":"BenchmarkIndexAnyASCII/1:4","Output":"=== RUN   BenchmarkIndexAnyASCII/1:4\n"}
+{"Action":"output","Test":"BenchmarkIndexAnyASCII/1:4","Output":"BenchmarkIndexAnyASCII/1:4\n"}
+{"Action":"output","Test":"BenchmarkIndexAnyASCII/1:4","Output":"BenchmarkIndexAnyASCII/1:4-16      \t172757770\t         7.092 ns/op\n"}
+{"Action":"output","Output":"PASS\n"}
+{"Action":"pass"}
diff --git a/src/cmd/internal/test2json/testdata/framebig.test b/src/cmd/internal/test2json/testdata/framebig.test
new file mode 100644
index 0000000000..cb0b11a6a0
--- /dev/null
+++ b/src/cmd/internal/test2json/testdata/framebig.test
@@ -0,0 +1,138 @@
+=== RUN   TestIndex
+--- PASS: TestIndex (0.00s)
+=== PASS  TestIndex
+=== NAME
+=== RUN   TestLastIndex
+--- PASS: TestLastIndex (0.00s)
+=== PASS  TestLastIndex
+=== NAME
+=== RUN   TestIndexAny
+--- PASS: TestIndexAny (0.00s)
+=== PASS  TestIndexAny
+=== NAME
+=== RUN   TestLastIndexAny
+--- PASS: TestLastIndexAny (0.00s)
+=== PASS  TestLastIndexAny
+=== NAME
+=== RUN   TestIndexByte
+--- PASS: TestIndexByte (0.00s)
+=== PASS  TestIndexByte
+=== NAME
+=== RUN   TestLastIndexByte
+--- PASS: TestLastIndexByte (0.00s)
+=== PASS  TestLastIndexByte
+=== NAME
+=== RUN   TestIndexRandom
+--- PASS: TestIndexRandom (0.00s)
+=== PASS  TestIndexRandom
+=== NAME
+=== RUN   TestIndexRune
+--- PASS: TestIndexRune (0.00s)
+=== PASS  TestIndexRune
+=== NAME
+=== RUN   TestIndexFunc
+--- PASS: TestIndexFunc (0.00s)
+=== PASS  TestIndexFunc
+=== NAME
+=== RUN   ExampleIndex
+--- PASS: ExampleIndex (0.00s)
+=== NAME
+=== RUN   ExampleIndexFunc
+--- PASS: ExampleIndexFunc (0.00s)
+=== NAME
+=== RUN   ExampleIndexAny
+--- PASS: ExampleIndexAny (0.00s)
+=== NAME
+=== RUN   ExampleIndexByte
+--- PASS: ExampleIndexByte (0.00s)
+=== NAME
+=== RUN   ExampleIndexRune
+--- PASS: ExampleIndexRune (0.00s)
+=== NAME
+=== RUN   ExampleLastIndex
+--- PASS: ExampleLastIndex (0.00s)
+=== NAME
+=== RUN   ExampleLastIndexAny
+--- PASS: ExampleLastIndexAny (0.00s)
+=== NAME
+=== RUN   ExampleLastIndexByte
+--- PASS: ExampleLastIndexByte (0.00s)
+=== NAME
+=== RUN   ExampleLastIndexFunc
+--- PASS: ExampleLastIndexFunc (0.00s)
+=== NAME
+goos: darwin
+goarch: amd64
+pkg: strings
+cpu: Intel(R) Core(TM) i9-9980HK CPU @ 2.40GHz
+=== RUN   BenchmarkIndexRune
+BenchmarkIndexRune
+BenchmarkIndexRune-16              	87335496	        14.27 ns/op
+=== NAME
+=== RUN   BenchmarkIndexRuneLongString
+BenchmarkIndexRuneLongString
+BenchmarkIndexRuneLongString-16    	57104472	        18.66 ns/op
+=== NAME
+=== RUN   BenchmarkIndexRuneFastPath
+BenchmarkIndexRuneFastPath
+BenchmarkIndexRuneFastPath-16      	262380160	         4.499 ns/op
+=== NAME
+=== RUN   BenchmarkIndex
+BenchmarkIndex
+BenchmarkIndex-16                  	248529364	         4.697 ns/op
+=== NAME
+=== RUN   BenchmarkLastIndex
+BenchmarkLastIndex
+BenchmarkLastIndex-16              	293688756	         4.166 ns/op
+=== NAME
+=== RUN   BenchmarkIndexByte
+BenchmarkIndexByte
+BenchmarkIndexByte-16              	310338391	         3.608 ns/op
+=== NAME
+=== RUN   BenchmarkIndexHard1
+BenchmarkIndexHard1
+BenchmarkIndexHard1-16             	   12852	     92380 ns/op
+=== NAME
+=== RUN   BenchmarkIndexHard2
+BenchmarkIndexHard2
+BenchmarkIndexHard2-16             	    8977	    135080 ns/op
+=== NAME
+=== RUN   BenchmarkIndexHard3
+BenchmarkIndexHard3
+BenchmarkIndexHard3-16             	    1885	    532079 ns/op
+=== NAME
+=== RUN   BenchmarkIndexHard4
+BenchmarkIndexHard4
+BenchmarkIndexHard4-16             	    2298	    533435 ns/op
+=== NAME
+=== RUN   BenchmarkLastIndexHard1
+BenchmarkLastIndexHard1
+BenchmarkLastIndexHard1-16         	     813	   1295767 ns/op
+=== NAME
+=== RUN   BenchmarkLastIndexHard2
+BenchmarkLastIndexHard2
+BenchmarkLastIndexHard2-16         	     784	   1389403 ns/op
+=== NAME
+=== RUN   BenchmarkLastIndexHard3
+BenchmarkLastIndexHard3
+BenchmarkLastIndexHard3-16         	     913	   1316608 ns/op
+=== NAME
+=== RUN   BenchmarkIndexTorture
+BenchmarkIndexTorture
+BenchmarkIndexTorture-16           	   98090	     10201 ns/op
+=== NAME
+=== RUN   BenchmarkIndexAnyASCII
+BenchmarkIndexAnyASCII
+=== RUN   BenchmarkIndexAnyASCII/1:1
+BenchmarkIndexAnyASCII/1:1
+BenchmarkIndexAnyASCII/1:1-16      	214829462	         5.592 ns/op
+=== NAME
+=== RUN   BenchmarkIndexAnyASCII/1:2
+BenchmarkIndexAnyASCII/1:2
+BenchmarkIndexAnyASCII/1:2-16      	155499682	         7.214 ns/op
+=== NAME
+=== RUN   BenchmarkIndexAnyASCII/1:4
+BenchmarkIndexAnyASCII/1:4
+BenchmarkIndexAnyASCII/1:4-16      	172757770	         7.092 ns/op
+=== NAME
+PASS
diff --git a/src/cmd/internal/test2json/testdata/framefuzz.json b/src/cmd/internal/test2json/testdata/framefuzz.json
new file mode 100644
index 0000000000..ea2eafa717
--- /dev/null
+++ b/src/cmd/internal/test2json/testdata/framefuzz.json
@@ -0,0 +1,68 @@
+{"Action":"run","Test":"TestAddrStringAllocs"}
+{"Action":"output","Test":"TestAddrStringAllocs","Output":"=== RUN   TestAddrStringAllocs\n"}
+{"Action":"run","Test":"TestAddrStringAllocs/zero"}
+{"Action":"output","Test":"TestAddrStringAllocs/zero","Output":"=== RUN   TestAddrStringAllocs/zero\n"}
+{"Action":"run","Test":"TestAddrStringAllocs/ipv4"}
+{"Action":"output","Test":"TestAddrStringAllocs/ipv4","Output":"=== RUN   TestAddrStringAllocs/ipv4\n"}
+{"Action":"run","Test":"TestAddrStringAllocs/ipv6"}
+{"Action":"output","Test":"TestAddrStringAllocs/ipv6","Output":"=== RUN   TestAddrStringAllocs/ipv6\n"}
+{"Action":"run","Test":"TestAddrStringAllocs/ipv6+zone"}
+{"Action":"output","Test":"TestAddrStringAllocs/ipv6+zone","Output":"=== RUN   TestAddrStringAllocs/ipv6+zone\n"}
+{"Action":"run","Test":"TestAddrStringAllocs/ipv4-in-ipv6"}
+{"Action":"output","Test":"TestAddrStringAllocs/ipv4-in-ipv6","Output":"=== RUN   TestAddrStringAllocs/ipv4-in-ipv6\n"}
+{"Action":"run","Test":"TestAddrStringAllocs/ipv4-in-ipv6+zone"}
+{"Action":"output","Test":"TestAddrStringAllocs/ipv4-in-ipv6+zone","Output":"=== RUN   TestAddrStringAllocs/ipv4-in-ipv6+zone\n"}
+{"Action":"output","Test":"TestAddrStringAllocs","Output":"--- PASS: TestAddrStringAllocs (0.00s)\n"}
+{"Action":"output","Test":"TestAddrStringAllocs/zero","Output":"    --- PASS: TestAddrStringAllocs/zero (0.00s)\n"}
+{"Action":"pass","Test":"TestAddrStringAllocs/zero"}
+{"Action":"output","Test":"TestAddrStringAllocs/ipv4","Output":"    --- PASS: TestAddrStringAllocs/ipv4 (0.00s)\n"}
+{"Action":"pass","Test":"TestAddrStringAllocs/ipv4"}
+{"Action":"output","Test":"TestAddrStringAllocs/ipv6","Output":"    --- PASS: TestAddrStringAllocs/ipv6 (0.00s)\n"}
+{"Action":"pass","Test":"TestAddrStringAllocs/ipv6"}
+{"Action":"output","Test":"TestAddrStringAllocs/ipv6+zone","Output":"    --- PASS: TestAddrStringAllocs/ipv6+zone (0.00s)\n"}
+{"Action":"pass","Test":"TestAddrStringAllocs/ipv6+zone"}
+{"Action":"output","Test":"TestAddrStringAllocs/ipv4-in-ipv6","Output":"    --- PASS: TestAddrStringAllocs/ipv4-in-ipv6 (0.00s)\n"}
+{"Action":"pass","Test":"TestAddrStringAllocs/ipv4-in-ipv6"}
+{"Action":"output","Test":"TestAddrStringAllocs/ipv4-in-ipv6+zone","Output":"    --- PASS: TestAddrStringAllocs/ipv4-in-ipv6+zone (0.00s)\n"}
+{"Action":"pass","Test":"TestAddrStringAllocs/ipv4-in-ipv6+zone"}
+{"Action":"pass","Test":"TestAddrStringAllocs"}
+{"Action":"run","Test":"TestPrefixString"}
+{"Action":"output","Test":"TestPrefixString","Output":"=== RUN   TestPrefixString\n"}
+{"Action":"output","Test":"TestPrefixString","Output":"--- PASS: TestPrefixString (0.00s)\n"}
+{"Action":"pass","Test":"TestPrefixString"}
+{"Action":"run","Test":"TestInvalidAddrPortString"}
+{"Action":"output","Test":"TestInvalidAddrPortString","Output":"=== RUN   TestInvalidAddrPortString\n"}
+{"Action":"output","Test":"TestInvalidAddrPortString","Output":"--- PASS: TestInvalidAddrPortString (0.00s)\n"}
+{"Action":"pass","Test":"TestInvalidAddrPortString"}
+{"Action":"run","Test":"TestAsSlice"}
+{"Action":"output","Test":"TestAsSlice","Output":"=== RUN   TestAsSlice\n"}
+{"Action":"output","Test":"TestAsSlice","Output":"--- PASS: TestAsSlice (0.00s)\n"}
+{"Action":"pass","Test":"TestAsSlice"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"Addr.string4\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"Prefix.isZero\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"IPv4Unspecified\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"joinHostPort\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"Addr.MarshalBinary\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"bePutUint64\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"mask6\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"AddrPort.isZero\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"stringsLastIndexByte\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"Addr.isZero\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"bePutUint32\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"leUint16\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"Addr.string6\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"beUint64\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"appendHexPad\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"lePutUint16\"\n"}
+{"Action":"output","Test":"TestInlining","Output":"--- PASS: TestInlining (0.10s)\n"}
+{"Action":"pass","Test":"TestInlining"}
+{"Action":"run","Test":"FuzzParse"}
+{"Action":"output","Test":"FuzzParse","Output":"=== RUN   FuzzParse\n"}
+{"Action":"output","Test":"FuzzParse","Output":"fuzz: elapsed: 0s, gathering baseline coverage: 0/390 completed\n"}
+{"Action":"output","Test":"FuzzParse","Output":"fuzz: elapsed: 0s, gathering baseline coverage: 390/390 completed, now fuzzing with 16 workers\n"}
+{"Action":"output","Test":"FuzzParse","Output":"fuzz: elapsed: 3s, execs: 438666 (146173/sec), new interesting: 12 (total: 402)\n"}
+{"Action":"output","Test":"FuzzParse","Output":"\u0003fuzz: elapsed: 4s, execs: 558467 (147850/sec), new interesting: 15 (total: 405)\n"}
+{"Action":"output","Test":"FuzzParse","Output":"--- PASS: FuzzParse (3.85s)\n"}
+{"Action":"pass","Test":"FuzzParse"}
+{"Action":"output","Output":"PASS\n"}
+{"Action":"pass"}
diff --git a/src/cmd/internal/test2json/testdata/framefuzz.test b/src/cmd/internal/test2json/testdata/framefuzz.test
new file mode 100644
index 0000000000..1eb3a125e2
--- /dev/null
+++ b/src/cmd/internal/test2json/testdata/framefuzz.test
@@ -0,0 +1,56 @@
+=== RUN   TestAddrStringAllocs
+=== RUN   TestAddrStringAllocs/zero
+=== NAME  TestAddrStringAllocs
+=== RUN   TestAddrStringAllocs/ipv4
+=== NAME  TestAddrStringAllocs
+=== RUN   TestAddrStringAllocs/ipv6
+=== NAME  TestAddrStringAllocs
+=== RUN   TestAddrStringAllocs/ipv6+zone
+=== NAME  TestAddrStringAllocs
+=== RUN   TestAddrStringAllocs/ipv4-in-ipv6
+=== NAME  TestAddrStringAllocs
+=== RUN   TestAddrStringAllocs/ipv4-in-ipv6+zone
+=== NAME  TestAddrStringAllocs
+--- PASS: TestAddrStringAllocs (0.00s)
+    --- PASS: TestAddrStringAllocs/zero (0.00s)
+    --- PASS: TestAddrStringAllocs/ipv4 (0.00s)
+    --- PASS: TestAddrStringAllocs/ipv6 (0.00s)
+    --- PASS: TestAddrStringAllocs/ipv6+zone (0.00s)
+    --- PASS: TestAddrStringAllocs/ipv4-in-ipv6 (0.00s)
+    --- PASS: TestAddrStringAllocs/ipv4-in-ipv6+zone (0.00s)
+=== NAME
+=== RUN   TestPrefixString
+--- PASS: TestPrefixString (0.00s)
+=== NAME
+=== RUN   TestInvalidAddrPortString
+--- PASS: TestInvalidAddrPortString (0.00s)
+=== NAME
+=== RUN   TestAsSlice
+--- PASS: TestAsSlice (0.00s)
+=== NAME
+=== NAME  TestInlining
+    inlining_test.go:102: not in expected set, but also inlinable: "Addr.string4"
+    inlining_test.go:102: not in expected set, but also inlinable: "Prefix.isZero"
+    inlining_test.go:102: not in expected set, but also inlinable: "IPv4Unspecified"
+    inlining_test.go:102: not in expected set, but also inlinable: "joinHostPort"
+    inlining_test.go:102: not in expected set, but also inlinable: "Addr.MarshalBinary"
+    inlining_test.go:102: not in expected set, but also inlinable: "bePutUint64"
+    inlining_test.go:102: not in expected set, but also inlinable: "mask6"
+    inlining_test.go:102: not in expected set, but also inlinable: "AddrPort.isZero"
+    inlining_test.go:102: not in expected set, but also inlinable: "stringsLastIndexByte"
+    inlining_test.go:102: not in expected set, but also inlinable: "Addr.isZero"
+    inlining_test.go:102: not in expected set, but also inlinable: "bePutUint32"
+    inlining_test.go:102: not in expected set, but also inlinable: "leUint16"
+    inlining_test.go:102: not in expected set, but also inlinable: "Addr.string6"
+    inlining_test.go:102: not in expected set, but also inlinable: "beUint64"
+    inlining_test.go:102: not in expected set, but also inlinable: "appendHexPad"
+    inlining_test.go:102: not in expected set, but also inlinable: "lePutUint16"
+--- PASS: TestInlining (0.10s)
+=== RUN   FuzzParse
+fuzz: elapsed: 0s, gathering baseline coverage: 0/390 completed
+fuzz: elapsed: 0s, gathering baseline coverage: 390/390 completed, now fuzzing with 16 workers
+fuzz: elapsed: 3s, execs: 438666 (146173/sec), new interesting: 12 (total: 402)
+fuzz: elapsed: 4s, execs: 558467 (147850/sec), new interesting: 15 (total: 405)
+--- PASS: FuzzParse (3.85s)
+=== NAME
+PASS
diff --git a/src/cmd/internal/test2json/testdata/timeout.json b/src/cmd/internal/test2json/testdata/timeout.json
new file mode 100644
index 0000000000..162a5bde44
--- /dev/null
+++ b/src/cmd/internal/test2json/testdata/timeout.json
@@ -0,0 +1,7 @@
+{"Action":"run","Test":"Test"}
+{"Action":"output","Test":"Test","Output":"=== RUN   Test\n"}
+{"Action":"output","Test":"Test","Output":"panic: test timed out after 1s\n"}
+{"Action":"output","Test":"Test","Output":"\n"}
+{"Action":"output","Output":"FAIL\tp\t1.111s\n"}
+{"Action":"output","Output":"FAIL\n"}
+{"Action":"fail"}
diff --git a/src/cmd/internal/test2json/testdata/timeout.test b/src/cmd/internal/test2json/testdata/timeout.test
new file mode 100644
index 0000000000..7f3debf37d
--- /dev/null
+++ b/src/cmd/internal/test2json/testdata/timeout.test
@@ -0,0 +1,5 @@
+=== RUN   Test
+panic: test timed out after 1s
+
+FAIL	p	1.111s
+FAIL