From 81f16ce89fa31bebfbba4c8569952a07bbbec5b5 Mon Sep 17 00:00:00 2001
From: Jamie Stephens <james_stephens@cable.comcast.com>
Date: Fri, 9 Jul 2021 18:43:53 +0000
Subject: [PATCH 1/3] Report broken test instead of panicking; closes #106

---
 dsl/js.go      | 12 +++++++-----
 dsl/js_test.go | 14 ++++++++++++++
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/dsl/js.go b/dsl/js.go
index 9f30f07..6073950 100644
--- a/dsl/js.go
+++ b/dsl/js.go
@@ -39,6 +39,10 @@ func JSExec(ctx *Ctx, src string, env map[string]interface{}) (interface{}, erro
 	return x, nil
 }
 
+func gojaPanic(vm *goja.Runtime, x interface{}) {
+	panic(vm.ToValue(x))
+}
+
 func jsExec(ctx *Ctx, src string, env map[string]interface{}) (interface{}, error) {
 
 	js := goja.New()
@@ -64,14 +68,14 @@ func jsExec(ctx *Ctx, src string, env map[string]interface{}) (interface{}, erro
 
 	js.Set("redactRegexp", func(pat string) {
 		if err := ctx.AddRedaction(pat); err != nil {
-			panic(err)
+			gojaPanic(js, Failure(err.Error()))
 		}
 	})
 
 	js.Set("redactString", func(pat string) {
 		pat = regexp.QuoteMeta(pat)
 		if err := ctx.AddRedaction(pat); err != nil {
-			panic(err)
+			gojaPanic(js, Failure(err.Error()))
 		}
 	})
 
@@ -81,9 +85,7 @@ func jsExec(ctx *Ctx, src string, env map[string]interface{}) (interface{}, erro
 		}
 		bss, err := match.Match(pat, msg, bs)
 		if err != nil {
-			// This panic is caught.  (That's how we
-			// return errors.)
-			panic(js.ToValue(err.Error()))
+			gojaPanic(js, Failure(err.Error()))
 		}
 		// Strip type (match.Bindings) to enable standard
 		// Javascript access to the maps.
diff --git a/dsl/js_test.go b/dsl/js_test.go
index c40f169..9c7d344 100644
--- a/dsl/js_test.go
+++ b/dsl/js_test.go
@@ -92,4 +92,18 @@ bss[0]["?x"] == "queso";
 		}
 	})
 
+	t.Run("nopanic", func(t *testing.T) {
+		// ToDo: Iterate over all exposed native Go functions?
+
+		src := `redactRegexp("[}");`
+
+		_, err := JSExec(ctx, src, nil)
+		if err == nil {
+			t.Fatal("should have complained (politely)")
+		}
+		if _, is := IsBroken(err); !is {
+			t.Fatalf("should have reported Broken instead of %T", err)
+		}
+	})
+
 }

From fb7cac084f7cdc7ce39aa541f1ca039ae2c30196 Mon Sep 17 00:00:00 2001
From: Jamie Stephens <james_stephens@cable.comcast.com>
Date: Fri, 9 Jul 2021 18:48:57 +0000
Subject: [PATCH 2/3] Document Failure()

---
 doc/manual.md | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/doc/manual.md b/doc/manual.md
index f651ce2..b48f6ee 100644
--- a/doc/manual.md
+++ b/doc/manual.md
@@ -605,7 +605,10 @@ single operation.  Currently the following steps are supported:
 		1. `redactString`: a function that compiles and adds a
            redaction pattern that matches the given string
            literally.
-		
+		   
+		1. `Failure`: return an object representing a failure with the
+           argument as the failure message.
+		   
 		1. `match`: [Sheen](https://github.com/Comcast/sheens)'s
             [pattern
             matching](https://github.com/Comcast/sheens#pattern-matching)

From 9957618ec8e12350e173638026960c34e8b9e48a Mon Sep 17 00:00:00 2001
From: Jamie Stephens <james_stephens@cable.comcast.com>
Date: Fri, 9 Jul 2021 19:03:50 +0000
Subject: [PATCH 3/3] Broken, not Failure

---
 dsl/js.go | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/dsl/js.go b/dsl/js.go
index 6073950..34f0dbd 100644
--- a/dsl/js.go
+++ b/dsl/js.go
@@ -68,14 +68,14 @@ func jsExec(ctx *Ctx, src string, env map[string]interface{}) (interface{}, erro
 
 	js.Set("redactRegexp", func(pat string) {
 		if err := ctx.AddRedaction(pat); err != nil {
-			gojaPanic(js, Failure(err.Error()))
+			gojaPanic(js, NewBroken(err))
 		}
 	})
 
 	js.Set("redactString", func(pat string) {
 		pat = regexp.QuoteMeta(pat)
 		if err := ctx.AddRedaction(pat); err != nil {
-			gojaPanic(js, Failure(err.Error()))
+			gojaPanic(js, NewBroken(err))
 		}
 	})
 
@@ -85,7 +85,7 @@ func jsExec(ctx *Ctx, src string, env map[string]interface{}) (interface{}, erro
 		}
 		bss, err := match.Match(pat, msg, bs)
 		if err != nil {
-			gojaPanic(js, Failure(err.Error()))
+			gojaPanic(js, NewBroken(err))
 		}
 		// Strip type (match.Bindings) to enable standard
 		// Javascript access to the maps.