Index: lldb/source/Utility/Args.cpp
===================================================================
--- lldb/source/Utility/Args.cpp
+++ lldb/source/Utility/Args.cpp
@@ -385,6 +385,7 @@
   };
 
   static ShellDescriptor g_Shells[] = {{ConstString("bash"), " '\"<>()&"},
+                                       {ConstString("fish"), " '\"<>()&\\|;"},
                                        {ConstString("tcsh"), " '\"<>()&$"},
                                        {ConstString("sh"), " '\"<>()&"}};
 
Index: lldb/unittests/Utility/ArgsTest.cpp
===================================================================
--- lldb/unittests/Utility/ArgsTest.cpp
+++ lldb/unittests/Utility/ArgsTest.cpp
@@ -331,6 +331,14 @@
   // Bash however doesn't need escaping for "$".
   EXPECT_EQ(Args::GetShellSafeArgument(bash, "a$b"), "a$b");
 
+  // Test escaping fish special characters.
+  FileSpec fish("/bin/fish", FileSpec::Style::posix);
+  EXPECT_EQ(Args::GetShellSafeArgument(fish, R"( '"<>()&\|;)"),
+            R"(\ \'\"\<\>\(\)\&\\\|\;)");
+  // Normal characters and expressions that shouldn't be escaped.
+  EXPECT_EQ(Args::GetShellSafeArgument(fish, "aA$1*"), "aA$1*");
+
+
   // Try escaping with an unknown shell.
   FileSpec unknown_shell("/bin/unknown_shell", FileSpec::Style::posix);
   EXPECT_EQ(Args::GetShellSafeArgument(unknown_shell, "a'b"), "a\\'b");