📄 cxaa012.a
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-- CXAA012.A---- Grant of Unlimited Rights---- Under contracts F33600-87-D-0337, F33600-84-D-0280, MDA903-79-C-0687,-- F08630-91-C-0015, and DCA100-97-D-0025, the U.S. Government obtained -- unlimited rights in the software and documentation contained herein.-- Unlimited rights are defined in DFAR 252.227-7013(a)(19). By making -- this public release, the Government intends to confer upon all -- recipients unlimited rights equal to those held by the Government. -- These rights include rights to use, duplicate, release or disclose the -- released technical data and computer software in whole or in part, in -- any manner and for any purpose whatsoever, and to have or permit others -- to do so.---- DISCLAIMER---- ALL MATERIALS OR INFORMATION HEREIN RELEASED, MADE AVAILABLE OR-- DISCLOSED ARE AS IS. THE GOVERNMENT MAKES NO EXPRESS OR IMPLIED -- WARRANTY AS TO ANY MATTER WHATSOEVER, INCLUDING THE CONDITIONS OF THE-- SOFTWARE, DOCUMENTATION OR OTHER INFORMATION RELEASED, MADE AVAILABLE -- OR DISCLOSED, OR THE OWNERSHIP, MERCHANTABILITY, OR FITNESS FOR A-- PARTICULAR PURPOSE OF SAID MATERIAL.--*---- OBJECTIVE:-- Check that the exception Mode_Error is raised when an attempt is made-- to read from (perform a Get_Line) or use the predefined End_Of_File -- function on a text file with mode Append_File.-- -- TEST DESCRIPTION:-- A scenario is created that demonstrates the potential for the -- incorrect usage of predefined text processing subprograms, resulting -- from their use with files of the wrong Mode. This results in the -- raising of Mode_Error exceptions, which is handled within blocks-- embedded in the test.-- A count is kept to ensure that each anticipated exception is in fact-- raised and handled properly.-- -- APPLICABILITY CRITERIA: -- This test is applicable only to implementations that support text-- files.---- -- CHANGE HISTORY:-- 06 Dec 94 SAIC ACVC 2.0-- 27 Feb 97 PWB.CTA Allowed for non-support of some IO operations--!with Ada.Text_IO;with Report;procedure CXAA012 is use Ada; Text_File : Text_IO.File_Type; Text_Filename : constant String := Report.Legal_File_Name ( Nam => "CXAA012" ); Incomplete : exception;begin Report.Test ("CXAA012", "Check that the exception Mode_Error is " & "raised when an attempt is made to read " & "from (perform a Get_Line) or use the " & "predefined End_Of_File function on a " & "text file with mode Append_File"); Test_for_Text_IO_Support: begin -- Use_Error or Name_Error will be raised if Text_IO operations -- or external files are not supported. Text_IO.Create (Text_File, Text_IO.Out_File, Text_Filename); exception when Text_IO.Use_Error | Text_IO.Name_Error => Report.Not_Applicable ( "Files not supported - Create as Out_File for Text_IO" ); raise Incomplete; end Test_for_Text_IO_Support; -- The application writes some amount of data to the file. Text_IO.Put_Line (Text_File, "Data entered into the file"); Text_IO.Close (Text_File); Operational_Test_Block: declare TC_Number_Of_Forced_Mode_Errors : constant Natural := 2; TC_Mode_Errors : Natural := 0; begin Text_IO.Open (Text_File, Text_IO.Append_File, Text_Filename); Test_for_Reading: declare TC_Data : String (1..80); TC_Length : Natural := 0; begin-- During the course of its processing, the application may become confused-- and erroneously attempt to read data from the file that is currently in-- Append_File mode (instead of the anticipated In_File mode).-- This would result in the raising of Mode_Error. Text_IO.Get_Line (Text_File, TC_Data, TC_Length); Report.Failed ("Exception not raised by Get_Line");-- An exception handler present within the application handles the exception-- and processing can continue. exception when Text_IO.Mode_Error => TC_Mode_Errors := TC_Mode_Errors + 1; when others => Report.Failed ("Exception in Get_Line processing"); end Test_for_Reading; Test_for_End_Of_File: declare TC_End_Of_File : Boolean; begin-- Again, during the course of its processing, the application attempts to -- call the End_Of_File function for the file that is currently in-- Append_File mode (instead of the anticipated In_File mode). TC_End_Of_File := Text_IO.End_Of_File (Text_File); Report.Failed ("Exception not raised by End_Of_File");-- Once again, an exception handler present within the application handles -- the exception and processing continues. exception when Text_IO.Mode_Error => TC_Mode_Errors := TC_Mode_Errors + 1; when others => Report.Failed("Exception in End_Of_File processing"); end Test_for_End_Of_File; if (TC_Mode_Errors /= TC_Number_Of_Forced_Mode_Errors) then Report.Failed ("Incorrect number of exceptions handled"); end if; end Operational_Test_Block; -- Delete the external file. if Text_IO.Is_Open (Text_File) then Text_IO.Delete (Text_File); else Text_IO.Open (Text_File, Text_IO.In_File, Text_Filename); Text_IO.Delete (Text_File); end if; Report.Result;exception when Incomplete => Report.Result; when others => Report.Failed ( "Unexpected exception" ); Report.Result;end CXAA012;
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