[llvm-cxxfilt][NFC] Use split-file to avoid echo abuse

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Author: keryell

llvm/docs/CommandGuide/llvm-cxxfilt.rst

@@ -54,8 +54,8 @@ OPTIONS
 
 .. option:: --quote
 
-  Add `"` `"` around demangled function symbols.
-  Do not quote already quoted symbols.
+  Add `"` `"` around demangled function symbols. Do not quote already quoted
+  symbols.
 
 .. option:: --no-strip-underscore, -n
 

llvm/test/tools/llvm-cxxfilt/quote.test

@@ -1,19 +1,24 @@
 // Show that llvm-cxxfilt --quote adds quotes around demangled symbols, unless the symbol is already quoted.
-RUN: echo _Z3barv '"_Z3barv"' > %t
-RUN: echo '"_Z3barv"' _Z3barv >> %t
-// This is not mangled, thus it should not be quoted
-RUN: echo 'log()' >> %t
-// Check that an "import thunk for" prefix can be quoted along the demangled name
-RUN: echo __imp__ZSt6futureIvE >> %t
-RUN: llvm-cxxfilt --quote < %t | FileCheck --match-full-lines --check-prefix=CHECK-FILE %s
+
+RUN: split-file %s %t
+
+RUN: llvm-cxxfilt --quote < %t/symbols-in-file.test | FileCheck --match-full-lines --check-prefix=CHECK-FILE %s
 CHECK-FILE: "bar()" "bar()"
 CHECK-FILE-NEXT: "bar()" "bar()"
-CHECK-FILE-NEXT: log()
-CHECK-FILE-NEXT: "import thunk for std::future<void>"
+CHECK-FILE: log()
+CHECK-FILE: "import thunk for std::future<void>"
 
-// Check it works with cli symbols too. Since a quoted mangled name is not a
+// Check it works with CLI symbols too. Since a quoted mangled name is not a
 // mangled name, it should be unchanged
 RUN: llvm-cxxfilt --quote _Z3firv '"_Z3barv"' 'saw()' | FileCheck --match-full-lines --check-prefix=CHECK-CLI %s
 CHECK-CLI: "fir()"
-CHECK-CLI: "_Z3barv"
-CHECK-CLI: saw()
+CHECK-CLI-NEXT: "_Z3barv"
+CHECK-CLI-NEXT: saw()
+
+//--- symbols-in-file.test
+_Z3barv "_Z3barv"
+"_Z3barv" _Z3barv
+// This is not mangled, thus it should not be quoted
+log()
+// Check that an "import thunk for" prefix can be quoted along the demangled name
+__imp__ZSt6futureIvE