[llvm-cov] Warn if -show-functions is used without query files
llvm-cov's report mode does not print any output when -show-functions is
specified and no source files are specified. This can be surprising, so
the tool should at least print out an error message when this happens.
rdar://problem/34636859
llvm-svn: 314175
diff --git a/llvm/test/tools/llvm-cov/report.cpp b/llvm/test/tools/llvm-cov/report.cpp
index af2ef98..4c35401 100644
--- a/llvm/test/tools/llvm-cov/report.cpp
+++ b/llvm/test/tools/llvm-cov/report.cpp
@@ -1,6 +1,9 @@
// RUN: llvm-cov report %S/Inputs/report.covmapping -instr-profile %S/Inputs/report.profdata -path-equivalence=,%S 2>&1 -show-region-summary -show-instantiation-summary | FileCheck %s
// RUN: llvm-cov report -show-functions %S/Inputs/report.covmapping -instr-profile %S/Inputs/report.profdata -path-equivalence=,%S %s 2>&1 | FileCheck -check-prefix=FILT %s
// RUN: llvm-cov report -show-functions %S/Inputs/report.covmapping -instr-profile %S/Inputs/report.profdata -path-equivalence=,%S %s does-not-exist.cpp 2>&1 | FileCheck -check-prefix=FILT %s
+// RUN: not llvm-cov report -show-functions %S/Inputs/report.covmapping -instr-profile %S/Inputs/report.profdata -path-equivalence=,%S 2>&1 | FileCheck -check-prefix=NO_FILES %s
+
+// NO_FILES: Source files must be specified when -show-functions=true is specified
// CHECK: Regions Missed Regions Cover Functions Missed Functions Executed Instantiations Missed Insts. Executed Lines Missed Lines Cover
// CHECK-NEXT: ---