RemoveFromList() should remove all matches

RemoveFromList() should remove all matches.  Before this commit,
RemoveFromList() only removes the first match.  This commit rewrites
RemoveFromList() so that it will remove all matches.  Besides, a unit
test is written.

Note: aosp/461936 wants to make sure libc.so precedes libdl.so in
DT_NEEDED entries.  However, if there are two "libdl" in shared_libs,
aosp/461936 won't achieve its goal because RemoveFromList() (prior to
this commit) only removes the first "libdl".

Bug: 62815515
Test: Build sailfish and check libstagefright.so
Change-Id: I9bec563cbf800bff4bd508fb21e28869a92cfe56

android/util.go

@@ -101,11 +101,18 @@ func RemoveListFromList(list []string, filter_out []string) (result []string) {
 
 func RemoveFromList(s string, list []string) (bool, []string) {
 	i := IndexList(s, list)
-	if i != -1 {
-		return true, append(list[:i], list[i+1:]...)
-	} else {
+	if i == -1 {
 		return false, list
 	}
+
+	result := make([]string, 0, len(list)-1)
+	result = append(result, list[:i]...)
+	for _, l := range list[i+1:] {
+		if l != s {
+			result = append(result, l)
+		}
+	}
+	return true, result
 }
 
 // FirstUniqueStrings returns all unique elements of a slice of strings, keeping the first copy of

android/util_test.go

@@ -300,3 +300,62 @@ func TestRemoveListFromList(t *testing.T) {
 		t.Errorf("       got: %#v", out)
 	}
 }
+
+func TestRemoveFromList(t *testing.T) {
+	testcases := []struct {
+		name          string
+		key           string
+		input         []string
+		expectedFound bool
+		expectedOut   []string
+	}{
+		{
+			name:          "remove_one_match",
+			key:           "a",
+			input:         []string{"a", "b", "c"},
+			expectedFound: true,
+			expectedOut:   []string{"b", "c"},
+		},
+		{
+			name:          "remove_three_matches",
+			key:           "a",
+			input:         []string{"a", "b", "a", "c", "a"},
+			expectedFound: true,
+			expectedOut:   []string{"b", "c"},
+		},
+		{
+			name:          "remove_zero_matches",
+			key:           "X",
+			input:         []string{"a", "b", "a", "c", "a"},
+			expectedFound: false,
+			expectedOut:   []string{"a", "b", "a", "c", "a"},
+		},
+		{
+			name:          "remove_all_matches",
+			key:           "a",
+			input:         []string{"a", "a", "a", "a"},
+			expectedFound: true,
+			expectedOut:   []string{},
+		},
+	}
+
+	for _, testCase := range testcases {
+		t.Run(testCase.name, func(t *testing.T) {
+			found, out := RemoveFromList(testCase.key, testCase.input)
+			if found != testCase.expectedFound {
+				t.Errorf("incorrect output:")
+				t.Errorf("       key: %#v", testCase.key)
+				t.Errorf("     input: %#v", testCase.input)
+				t.Errorf("  expected: %#v", testCase.expectedFound)
+				t.Errorf("       got: %#v", found)
+			}
+			if !reflect.DeepEqual(out, testCase.expectedOut) {
+				t.Errorf("incorrect output:")
+				t.Errorf("       key: %#v", testCase.key)
+				t.Errorf("     input: %#v", testCase.input)
+				t.Errorf("  expected: %#v", testCase.expectedOut)
+				t.Errorf("       got: %#v", out)
+			}
+		})
+	}
+}