From a7ebc2f9fe8537369926f6aab9b77062dcf4b8d9 Mon Sep 17 00:00:00 2001
From: Ger Hobbelt <ger@hobbelt.com>
Date: Tue, 18 Jun 2019 20:16:20 +0200
Subject: [PATCH 1/3] when `sourceContentFor(aSource, nullOnMissing=false)`
 shouldn't this situation also throw an exception? In the other situation,
 where this API might also produce a NULL return, an exception *is* thrown
 instead, so this looks to me like the more consistent behaviour.

---
 lib/source-map-consumer.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/source-map-consumer.js b/lib/source-map-consumer.js
index 9b68e393..63069a1c 100644
--- a/lib/source-map-consumer.js
+++ b/lib/source-map-consumer.js
@@ -527,7 +527,11 @@ class BasicSourceMapConsumer extends SourceMapConsumer {
    */
   sourceContentFor(aSource, nullOnMissing) {
     if (!this.sourcesContent) {
-      return null;
+      if (nullOnMissing) {
+        return null;
+      }
+
+      throw new Error('"' + aSource + '" is not in the SourceMap.');
     }
 
     const index = this._findSourceIndex(aSource);

From b974ff23309d316ffda169f11b684e9cc7468af0 Mon Sep 17 00:00:00 2001
From: Ger Hobbelt <ger@hobbelt.com>
Date: Tue, 18 Jun 2019 20:37:54 +0200
Subject: [PATCH 2/3] allow the sourceMapGenerator code to also enjoy the
 `nullOrMissing` argument/option for the `consumer.sourceContentFor()` API.

---
 lib/source-map-generator.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/source-map-generator.js b/lib/source-map-generator.js
index 8111e061..6851701b 100644
--- a/lib/source-map-generator.js
+++ b/lib/source-map-generator.js
@@ -79,7 +79,7 @@ class SourceMapGenerator {
         generator._sources.add(sourceRelative);
       }
 
-      const content = aSourceMapConsumer.sourceContentFor(sourceFile);
+      const content = aSourceMapConsumer.sourceContentFor(sourceFile, true);
       if (content != null) {
         generator.setSourceContent(sourceFile, content);
       }
@@ -238,7 +238,7 @@ class SourceMapGenerator {
 
     // Copy sourcesContents of applied map.
     aSourceMapConsumer.sources.forEach(function(srcFile) {
-      const content = aSourceMapConsumer.sourceContentFor(srcFile);
+      const content = aSourceMapConsumer.sourceContentFor(srcFile, true);
       if (content != null) {
         if (aSourceMapPath != null) {
           srcFile = util.join(aSourceMapPath, srcFile);

From d2c33d1c9a38f69e4448bdae4e9448cb00c7a3eb Mon Sep 17 00:00:00 2001
From: Ger Hobbelt <ger@hobbelt.com>
Date: Tue, 18 Jun 2019 20:48:15 +0200
Subject: [PATCH 3/3] also use the `nullOrNothing` option/argument in the
 lib/source-node.js code to restore intended behaviour. All tests pass.

---
 lib/source-node.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/source-node.js b/lib/source-node.js
index 8a7a157e..8f92c0a1 100644
--- a/lib/source-node.js
+++ b/lib/source-node.js
@@ -137,7 +137,7 @@ class SourceNode {
 
     // Copy sourcesContent into SourceNode
     aSourceMapConsumer.sources.forEach(function(sourceFile) {
-      const content = aSourceMapConsumer.sourceContentFor(sourceFile);
+      const content = aSourceMapConsumer.sourceContentFor(sourceFile, true);
       if (content != null) {
         if (aRelativePath != null) {
           sourceFile = util.join(aRelativePath, sourceFile);