diff --git a/CHANGELOG.md b/CHANGELOG.md
index fae032d..1178530 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,20 @@
 # 1.2.6
 
 * Properly format trailing commas in assertions.
+* Improve indentation of adjacent strings. This fixes a regression introduced
+  in 1.2.5 and hopefully makes adjacent strings generally look better.
+
+  Adjacent strings in argument lists now format the same regardless of whether
+  the argument list contains a trailing comma. The rule is that if the
+  argument list contains no other strings, then the adjacent strings do not
+  get extra indentation. This keeps them lined up when doing so is unlikely to
+  be confused as showing separate independent string arguments.
+
+  Previously, adjacent strings were never indented in argument lists without a
+  trailing comma and always in argument lists that did. With this change,
+  adjacent strings are still always indented in collection literals because
+  readers are likely to interpret a series of unindented lines there as showing
+  separate collection elements.
 
 # 1.2.5
 
diff --git a/lib/src/source_visitor.dart b/lib/src/source_visitor.dart
index c3f1525..d31f6b8 100644
--- a/lib/src/source_visitor.dart
+++ b/lib/src/source_visitor.dart
@@ -186,9 +186,72 @@
   }
 
   visitAdjacentStrings(AdjacentStrings node) {
+    // We generally want to indent adjacent strings because it can be confusing
+    // otherwise when they appear in a list of expressions, like:
+    //
+    //     [
+    //       "one",
+    //       "two"
+    //       "three",
+    //       "four"
+    //     ]
+    //
+    // Especially when these stings are longer, it can be hard to tell that
+    // "three" is a continuation of the previous argument.
+    //
+    // However, the indentation is distracting in argument lists that don't
+    // suffer from this ambiguity:
+    //
+    //     test(
+    //         "A very long test description..."
+    //             "this indentation looks bad.", () { ... });
+    //
+    // To balance these, we omit the indentation when an adjacent string
+    // expression is the only string in an argument list.
+    var shouldNest = true;
+
+    isString(AstNode node) => node is StringLiteral || node is AdjacentStrings;
+
+    var parent = node.parent;
+    if (parent is ArgumentList) {
+      shouldNest = false;
+
+      for (var argument in parent.arguments) {
+        if (argument == node) continue;
+        if (isString(argument)) {
+          shouldNest = true;
+          break;
+        }
+      }
+    } else if (parent is Assertion) {
+      // Treat asserts like argument lists.
+      shouldNest = false;
+      if (parent.condition != node && isString(parent.condition)) {
+        shouldNest = true;
+      }
+
+      if (parent.message != node && isString(parent.message)) {
+        shouldNest = true;
+      }
+    } else if (parent is VariableDeclaration ||
+        parent is AssignmentExpression &&
+            parent.rightHandSide == node &&
+            parent.parent is ExpressionStatement) {
+      // Don't add extra indentation in a variable initializer or assignment:
+      //
+      //     var variable =
+      //         "no extra"
+      //         "indent";
+      shouldNest = false;
+    } else if (parent is NamedExpression) {
+      shouldNest = false;
+    }
+
     builder.startSpan();
     builder.startRule();
+    if (shouldNest) builder.nestExpression();
     visitNodes(node.strings, between: splitOrNewline);
+    if (shouldNest) builder.unnest();
     builder.endRule();
     builder.endSpan();
   }
diff --git a/test/regression/0100/0185.stmt b/test/regression/0100/0185.stmt
index aac3da2..29a2b7a 100644
--- a/test/regression/0100/0185.stmt
+++ b/test/regression/0100/0185.stmt
@@ -9,6 +9,6 @@
 const NO_DART_SCRIPT_AND_EXPERIMENTAL = const MessageTemplate(
     const MessageId('polymer', 6),
     'The experimental bootstrap feature doesn\'t support script tags on '
-    'the main document (for now).',
+        'the main document (for now).',
     'Script tags with experimental bootstrap',
     'This experimental feature is no longer supported.');
\ No newline at end of file
diff --git a/test/regression/0200/0211.unit b/test/regression/0200/0211.unit
index 01766d8..aad9674 100644
--- a/test/regression/0200/0211.unit
+++ b/test/regression/0200/0211.unit
@@ -24,7 +24,7 @@
   JS(
       'void',
       'Object.defineProperty(#, #, '
-      '{value: #, enumerable: false, writable: true, configurable: true})',
+          '{value: #, enumerable: false, writable: true, configurable: true})',
       obj,
       property,
       value);
diff --git a/test/regression/0400/0467.unit b/test/regression/0400/0467.unit
index 57df4c3..29ef4f3 100644
--- a/test/regression/0400/0467.unit
+++ b/test/regression/0400/0467.unit
@@ -19,8 +19,7 @@
   void showNodesAndEntryPoints([_, __]) {
     addAll(
         'nodesAndEntryPoints',
-        new PolymerDom(this).children.map((child) =>
-            '${child.outerHtml} ------> '
+        new PolymerDom(this).children.map((child) => '${child.outerHtml} ------> '
             '${(new PolymerDom(child).getDestinationInsertionPoints()[0] as Element).outerHtml}'));
   }
 }
\ No newline at end of file
diff --git a/test/regression/0700/0705.stmt b/test/regression/0700/0705.stmt
new file mode 100644
index 0000000..38f2fd2
--- /dev/null
+++ b/test/regression/0700/0705.stmt
@@ -0,0 +1,10 @@
+>>>
+final _appUrl = Platform.isIOS
+    ? 'https://itunes.apple.com/us/app/google-adwords/id1037457231'
+    : 'https://play.google.com/store/apps/details?id=com.google.android.apps.'
+    'adwords';
+<<<
+final _appUrl = Platform.isIOS
+    ? 'https://itunes.apple.com/us/app/google-adwords/id1037457231'
+    : 'https://play.google.com/store/apps/details?id=com.google.android.apps.'
+        'adwords';
\ No newline at end of file
diff --git a/test/regression/0700/0799.unit b/test/regression/0700/0799.unit
new file mode 100644
index 0000000..acd54a4
--- /dev/null
+++ b/test/regression/0700/0799.unit
@@ -0,0 +1,14 @@
+>>>
+@ShouldThrow(
+  'Could not generate `toJson` code for `watch`.\n'
+  'None of the provided `TypeHelper` instances support the defined type.',
+  configurations: ['default'],
+)
+class C {}
+<<<
+@ShouldThrow(
+  'Could not generate `toJson` code for `watch`.\n'
+  'None of the provided `TypeHelper` instances support the defined type.',
+  configurations: ['default'],
+)
+class C {}
\ No newline at end of file
diff --git a/test/regression/other/flutter.unit b/test/regression/other/flutter.unit
new file mode 100644
index 0000000..98dbde8
--- /dev/null
+++ b/test/regression/other/flutter.unit
@@ -0,0 +1,18 @@
+>>>
+const Vendor _trevor = Vendor(
+    name: 'Trevor’s shop',
+    avatarAsset: 'people/square/trevor.png',
+    avatarAssetPackage: _kGalleryAssetsPackage,
+    description:
+        'Trevor makes great stuff for awesome people like you. Super cool and extra '
+            'awesome all of his shop’s goods are handmade with love. Custom orders are '
+            'available upon request if you need something extra special.');
+<<<
+const Vendor _trevor = Vendor(
+    name: 'Trevor’s shop',
+    avatarAsset: 'people/square/trevor.png',
+    avatarAssetPackage: _kGalleryAssetsPackage,
+    description:
+        'Trevor makes great stuff for awesome people like you. Super cool and extra '
+        'awesome all of his shop’s goods are handmade with love. Custom orders are '
+        'available upon request if you need something extra special.');
\ No newline at end of file
diff --git a/test/whitespace/adjacent_strings.stmt b/test/whitespace/adjacent_strings.stmt
new file mode 100644
index 0000000..40d5da1
--- /dev/null
+++ b/test/whitespace/adjacent_strings.stmt
@@ -0,0 +1,232 @@
+40 columns                              |
+>>> do not indent adjacent strings if other args are not strings
+function(
+    notString,
+    "adjacent"
+    "string");
+<<<
+function(
+    notString,
+    "adjacent"
+    "string");
+>>> do not indent adjacent strings if other args are not strings
+function(
+    notString,
+    "adjacent"
+    "string",);
+<<<
+function(
+  notString,
+  "adjacent"
+  "string",
+);
+>>> do indent adjacent strings if other arg is string
+function(
+    "string",
+    notString,
+    "adjacent"
+    "string");
+<<<
+function(
+    "string",
+    notString,
+    "adjacent"
+        "string");
+>>> do indent adjacent strings if other arg is string
+function(
+    "string",
+    notString,
+    "adjacent"
+    "string",);
+<<<
+function(
+  "string",
+  notString,
+  "adjacent"
+      "string",
+);
+>>> do indent adjacent strings if other arg is string interpolation
+function(
+    "${str}${ing}",
+    notString,
+    "adjacent"
+    "string");
+<<<
+function(
+    "${str}${ing}",
+    notString,
+    "adjacent"
+        "string");
+>>> do indent adjacent strings if other arg is adjacent string
+function(
+    "adjacent"
+    "string",
+    notString,
+    "adjacent"
+    "string");
+<<<
+function(
+    "adjacent"
+        "string",
+    notString,
+    "adjacent"
+        "string");
+>>> always indent adjacent strings in list
+var list = [
+  "adjacent"
+  "string",
+  "another"
+  "adjacent"
+  "string"
+];
+<<<
+var list = [
+  "adjacent"
+      "string",
+  "another"
+      "adjacent"
+      "string"
+];
+>>> always indent adjacent strings in map key
+var map = {
+  "adjacent"
+  "string": value,
+  "another"
+  "adjacent"
+  "string": value
+};
+<<<
+var map = {
+  "adjacent"
+      "string": value,
+  "another"
+      "adjacent"
+      "string": value
+};
+>>> always indent adjacent strings in map value
+var map = {
+  key: "adjacent"
+  "string",
+  key: "another"
+  "adjacent"
+  "string"
+};
+<<<
+var map = {
+  key: "adjacent"
+      "string",
+  key: "another"
+      "adjacent"
+      "string"
+};
+>>> always indent adjacent strings in set
+var set = {
+  "adjacent"
+  "string",
+  "another"
+  "adjacent"
+  "string"
+};
+<<<
+var set = {
+  "adjacent"
+      "string",
+  "another"
+      "adjacent"
+      "string"
+};
+>>> don't indent in => body
+main() => "adjacent"
+"string";
+<<<
+main() => "adjacent"
+    "string";
+>>> indent in then branch of ?:
+var string = c ? "adjacent"
+"string" : "other";
+<<<
+var string = c
+    ? "adjacent"
+        "string"
+    : "other";
+>>> indent in else branch of ?:
+var string = c ? "other" : "adjacent"
+"string";
+<<<
+var string = c
+    ? "other"
+    : "adjacent"
+        "string";
+>>> don't indent in initializer
+var longVariableName = "very long adjacent"
+"string";
+<<<
+var longVariableName =
+    "very long adjacent"
+    "string";
+>>> don't indent assignment in statement position
+long.receiver.expression = "very long adjacent"
+"string";
+<<<
+long.receiver.expression =
+    "very long adjacent"
+    "string";
+>>> string interpolation counts as a string
+function(
+    "adjacent"
+    "string",
+    "${str}${ing}");
+<<<
+function(
+    "adjacent"
+        "string",
+    "${str}${ing}");
+>>> another adjacent string counts as a string
+function(
+    "adjacent"
+    "string",
+    "another"
+    "adjacent");
+<<<
+function(
+    "adjacent"
+        "string",
+    "another"
+        "adjacent");
+>>> do not indent adjacent strings in assert if other args are not strings
+assert(
+    condition,
+    "adjacent"
+    "string");
+<<<
+assert(
+    condition,
+    "adjacent"
+    "string");
+>>> don't need extra indentation inside named arguments
+function(named: "adjacent"
+"string",
+another: "adjacent"
+"string"
+"more");
+<<<
+function(
+    named: "adjacent"
+        "string",
+    another: "adjacent"
+        "string"
+        "more");
+>>> don't need extra indentation inside named arguments
+function(named: "adjacent"
+"string",
+another: "adjacent"
+"string"
+"more",);
+<<<
+function(
+  named: "adjacent"
+      "string",
+  another: "adjacent"
+      "string"
+      "more",
+);
\ No newline at end of file