[flang-commits] [flang] [llvm] [flang] [flang-rt] Implement AT edit descriptor for Fortran 202X with appropriate handling and tests (PR #189157)

[Eugene Epshteyn via flang-commits]

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@@ -0,0 +1,40 @@
+! RUN: %python %S/test_errors.py %s %flang_fc1 -pedantic
+! Test AT edit descriptor (Fortran 202X)
+
+  character(10) :: str
+  character(kind=2,len=10) :: str2
+  character(kind=4,len=10) :: str4
+
+  ! Valid: AT with WRITE
+  write(*, '(AT)') 'hello'
+  write(*, '(AT)') str
+  write(*, '(2AT)') 'abc', 'def'
+
+  ! Valid: AT with non-default character kinds
+  write(*, '(AT)') str2
+  write(*, '(AT)') str4
+  write(*, '(2AT)') str2, str4
+
+  ! Valid: AT in FORMAT statement for WRITE
+1 format(AT)
+  write(*,1) 'hello'
+
+  ! Error: AT must not be used for input
+  !ERROR: 'AT' edit descriptor must not be used for input
+  read(*, '(AT)') str
+
+  ! Error: AT must not be used for input with non-default kinds
+  !ERROR: 'AT' edit descriptor must not be used for input
+  read(*, '(AT)') str2
+  !ERROR: 'AT' edit descriptor must not be used for input
+  read(*, '(AT)') str4
+
+  ! AT does not accept a width
+  !ERROR: 'AT' edit descriptor does not accept a width value
+  write(*, '(AT10)') str
+
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eugeneepshteyn wrote:

Please also add a test for something like `AT10.2`. Should this be an error, or ignore it?

https://github.com/llvm/llvm-project/pull/189157