Simplify self.emcc() test method. NFC (#16550)

This avoids adding a default `-o` and therefore falls back to emcc/clang
defaults or `foo.o` rather than `foo.c.o`.

I also simplified some of the tests that call this function to make them
(I think) more readable.

Author: sbc100

tests/common.py

@@ -904,10 +904,10 @@ def run_process(self, cmd, check=True, **args):
         self.fail(f'subprocess exited with non-zero return code({e.returncode}): `{shared.shlex_join(cmd)}`')
 
   def emcc(self, filename, args=[], output_filename=None, **kwargs):
-    if output_filename is None:
-      output_filename = filename + '.o'
-    try_delete(output_filename)
-    self.run_process([compiler_for(filename), filename] + args + ['-o', output_filename], **kwargs)
+    cmd = [compiler_for(filename), filename] + args
+    if output_filename:
+      cmd += ['-o', output_filename]
+    self.run_process(cmd, **kwargs)
 
   # Shared test code between main suite and others
 

tests/test_core.py

@@ -853,10 +853,10 @@ def test_multiply_defined_symbols(self):
     self.emcc('b2.c', ['-c'])
     self.emcc('main.c', ['-c'])
 
-    building.emar('cr', 'liba.a', ['a1.c.o', 'a2.c.o'])
-    building.emar('cr', 'libb.a', ['b1.c.o', 'b2.c.o'])
+    building.emar('cr', 'liba.a', ['a1.o', 'a2.o'])
+    building.emar('cr', 'libb.a', ['b1.o', 'b2.o'])
 
-    building.link_to_object(['main.c.o', 'liba.a', 'libb.a'], 'all.o')
+    building.link_to_object(['main.o', 'liba.a', 'libb.a'], 'all.o')
 
     self.emcc('all.o', self.get_emcc_args(), 'all.js')
     self.do_run('all.js', 'result: 1', no_build=True)

tests/test_other.py

@@ -992,14 +992,10 @@ def test_symlink_has_bad_suffix(self):
     self.assertContained('unknown file type: foobar.xxx', err)
 
   def test_multiply_defined_libsymbols(self):
-    lib_name = 'libA.c'
-    a2_name = 'a2.c'
-    b2_name = 'b2.c'
-    main_name = 'main.c'
-    create_file(lib_name, 'int mult() { return 1; }')
-    create_file(a2_name, 'void x() {}')
-    create_file(b2_name, 'void y() {}')
-    create_file(main_name, r'''
+    create_file('libA.c', 'int mult() { return 1; }')
+    create_file('a2.c', 'void x() {}')
+    create_file('b2.c', 'void y() {}')
+    create_file('main.c', r'''
       #include <stdio.h>
       int mult();
       int main() {
@@ -1008,26 +1004,20 @@ def test_multiply_defined_libsymbols(self):
       }
     ''')
 
-    self.emcc(lib_name, ['-shared'], output_filename='libA.so')
+    self.emcc('libA.c', ['-shared'], output_filename='libA.so')
 
-    self.emcc(a2_name, ['-r', '-L.', '-lA'])
-    self.emcc(b2_name, ['-r', '-L.', '-lA'])
+    self.emcc('a2.c', ['-r', '-L.', '-lA', '-o', 'a2.o'])
+    self.emcc('b2.c', ['-r', '-L.', '-lA', '-o', 'b2.o'])
 
-    self.emcc(main_name, ['-L.', '-lA', a2_name + '.o', b2_name + '.o'], output_filename='a.out.js')
+    self.emcc('main.c', ['-L.', '-lA', 'a2.o', 'b2.o'])
 
     self.assertContained('result: 1', self.run_js('a.out.js'))
 
   def test_multiply_defined_libsymbols_2(self):
-    a = "int x() { return 55; }"
-    a_name = 'a.c'
-    create_file(a_name, a)
-    b = "int y() { return 2; }"
-    b_name = 'b.c'
-    create_file(b_name, b)
-    c = "int z() { return 5; }"
-    c_name = 'c.c'
-    create_file(c_name, c)
-    main = r'''
+    create_file('a.c', "int x() { return 55; }")
+    create_file('b.c', "int y() { return 2; }")
+    create_file('c.c', "int z() { return 5; }")
+    create_file('main.c', r'''
       #include <stdio.h>
       int x();
       int y();
@@ -1036,18 +1026,15 @@ def test_multiply_defined_libsymbols_2(self):
         printf("result: %d\n", x() + y() + z());
         return 0;
       }
-    '''
-    main_name = 'main.c'
-    create_file(main_name, main)
+    ''')
 
-    self.emcc(a_name, ['-c']) # a.c.o
-    self.emcc(b_name, ['-c']) # b.c.o
-    self.emcc(c_name, ['-c']) # c.c.o
-    lib_name = 'libLIB.a'
-    building.emar('cr', lib_name, [a_name + '.o', b_name + '.o']) # libLIB.a with a and b
+    self.emcc('a.c', ['-c']) # a.o
+    self.emcc('b.c', ['-c']) # b.o
+    self.emcc('c.c', ['-c']) # c.o
+    building.emar('cr', 'libLIB.a', ['a.o', 'b.o']) # libLIB.a with a and b
 
     # a is in the lib AND in an .o, so should be ignored in the lib. We do still need b from the lib though
-    self.emcc(main_name, [a_name + '.o', c_name + '.o', '-L.', '-lLIB'], output_filename='a.out.js')
+    self.emcc('main.c', ['a.o', 'c.o', '-L.', '-lLIB'])
 
     self.assertContained('result: 62', self.run_js('a.out.js'))
 
@@ -1063,9 +1050,9 @@ def test_link_group(self):
       }
     ''')
 
-    self.emcc('lib.c', ['-c']) # lib.c.o
+    self.emcc('lib.c', ['-c']) # lib.o
     lib_name = 'libLIB.a'
-    building.emar('cr', lib_name, ['lib.c.o']) # libLIB.a with lib.c.o
+    building.emar('cr', lib_name, ['lib.o']) # libLIB.a with lib.o
 
     def test(compiler, main_name, lib_args, err_expected):
       print(err_expected)
@@ -1350,9 +1337,7 @@ def test_identical_basenames(self):
 
   def test_main_a(self):
     # if main() is in a .a, we need to pull in that .a
-
-    main_name = 'main.c'
-    create_file(main_name, r'''
+    create_file('main.c', r'''
       #include <stdio.h>
       extern int f();
       int main() {
@@ -1361,18 +1346,17 @@ def test_main_a(self):
       }
     ''')
 
-    other_name = 'other.c'
-    create_file(other_name, r'''
+    create_file('other.c', r'''
       #include <stdio.h>
       int f() { return 12346; }
     ''')
 
-    self.run_process([EMCC, main_name, '-c', '-o', main_name + '.o'])
-    self.run_process([EMCC, other_name, '-c', '-o', other_name + '.o'])
+    self.run_process([EMCC, '-c', 'main.c'])
+    self.run_process([EMCC, '-c', 'other.c'])
 
-    self.run_process([EMAR, 'cr', main_name + '.a', main_name + '.o'])
+    self.run_process([EMAR, 'cr', 'libmain.a', 'main.o'])
 
-    self.run_process([EMCC, other_name + '.o', main_name + '.a'])
+    self.run_process([EMCC, 'other.o', 'libmain.a'])
 
     self.assertContained('result: 12346.', self.run_js('a.out.js'))