Add ASCII character table

closes #36

3 files changed, 79 insertions, 12 deletions

diff --git a/src/lib.rs b/src/lib.rs
index c63485b..2edae33 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -26,6 +26,7 @@ pub enum ByteCategory {
 #[non_exhaustive]
 pub enum CharacterTable {
     Default,
+    Ascii,
     CP437,
 }
 
@@ -83,6 +84,14 @@ impl Byte {
                 AsciiOther => '•',
                 NonAscii => '×',
             },
+            CharacterTable::Ascii => match self.category() {
+                Null => '.',
+                AsciiPrintable => self.0 as char,
+                AsciiWhitespace if self.0 == 0x20 => ' ',
+                AsciiWhitespace => '.',
+                AsciiOther => '.',
+                NonAscii => '.',
+            },
             CharacterTable::CP437 => CP437[self.0 as usize],
         }
     }
diff --git a/src/main.rs b/src/main.rs
index 7cabed2..ddb4500 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -145,6 +145,21 @@ fn run() -> Result<()> {
                 .help("Show the character panel on the right. This is the default, unless --no-characters has been specified."),
         )
         .arg(
+            Arg::new("character-table")
+                .long("character-table")
+                .value_name("FORMAT")
+                .value_parser(["default", "ascii", "codepage-437"])
+                .default_value("default")
+                .help(
+                    "Defines how bytes are mapped to characters:\n  \
+                    \"default\": show printable ASCII characters as-is, '⋄' for NULL bytes, \
+                    ' ' for space, '_' for other ASCII whitespace, \
+                    '•' for other ASCII characters, and '×' for non-ASCII bytes.\n  \
+                    \"ascii\": show printable ASCII as-is, ' ' for space, '.' for everything else.\n  \
+                    \"codepage-437\": uses code page 437 (for non-ASCII bytes).\n"
+                ),
+        )
+        .arg(
             Arg::new("no_position")
                 .short('P')
                 .long("no-position")
@@ -214,18 +229,6 @@ fn run() -> Result<()> {
                 .help("An alias for '--endianness=little'."),
         )
         .arg(
-            Arg::new("character-table")
-                .long("character-table")
-                .value_name("FORMAT")
-                .value_parser(["default", "codepage-437"])
-                .default_value("default")
-                .help(
-                    "The character table that should be used. 'default' \
-                    will show dots for non-ASCII characters, 'codepage-437' \
-                    will use code page 437 for those characters."
-                ),
-        )
-        .arg(
             Arg::new("base")
                 .short('b')
                 .long("base")
@@ -497,6 +500,7 @@ fn run() -> Result<()> {
         .as_ref()
     {
         "default" => CharacterTable::Default,
+        "ascii" => CharacterTable::Ascii,
         "codepage-437" => CharacterTable::CP437,
         _ => unreachable!(),
     };
diff --git a/tests/integration_tests.rs b/tests/integration_tests.rs
index a44c77c..1115528 100644
--- a/tests/integration_tests.rs
+++ b/tests/integration_tests.rs
@@ -624,6 +624,60 @@ mod character_table {
     use super::PrettyAssert;
 
     #[test]
+    fn ascii() {
+        hexyl()
+            .arg("hello_world_elf64")
+            .arg("--color=never")
+            .arg("--character-table=ascii")
+            .assert()
+            .success()
+            .pretty_stdout(
+                "┌────────┬─────────────────────────┬─────────────────────────┬────────┬────────┐
+│00000000│ 7f 45 4c 46 02 01 01 00 ┊ 00 00 00 00 00 00 00 00 │.ELF....┊........│
+│00000010│ 02 00 3e 00 01 00 00 00 ┊ 00 10 40 00 00 00 00 00 │..>.....┊..@.....│
+│00000020│ 40 00 00 00 00 00 00 00 ┊ 28 20 00 00 00 00 00 00 │@.......┊( ......│
+│00000030│ 00 00 00 00 40 00 38 00 ┊ 03 00 40 00 04 00 03 00 │....@.8.┊..@.....│
+│00000040│ 01 00 00 00 04 00 00 00 ┊ 00 00 00 00 00 00 00 00 │........┊........│
+│00000050│ 00 00 40 00 00 00 00 00 ┊ 00 00 40 00 00 00 00 00 │..@.....┊..@.....│
+│00000060│ e8 00 00 00 00 00 00 00 ┊ e8 00 00 00 00 00 00 00 │........┊........│
+│00000070│ 00 10 00 00 00 00 00 00 ┊ 01 00 00 00 05 00 00 00 │........┊........│
+│00000080│ 00 10 00 00 00 00 00 00 ┊ 00 10 40 00 00 00 00 00 │........┊..@.....│
+│00000090│ 00 10 40 00 00 00 00 00 ┊ 1d 00 00 00 00 00 00 00 │..@.....┊........│
+│000000a0│ 1d 00 00 00 00 00 00 00 ┊ 00 10 00 00 00 00 00 00 │........┊........│
+│000000b0│ 01 00 00 00 06 00 00 00 ┊ 00 20 00 00 00 00 00 00 │........┊. ......│
+│000000c0│ 00 20 40 00 00 00 00 00 ┊ 00 20 40 00 00 00 00 00 │. @.....┊. @.....│
+│000000d0│ 0e 00 00 00 00 00 00 00 ┊ 0e 00 00 00 00 00 00 00 │........┊........│
+│000000e0│ 00 10 00 00 00 00 00 00 ┊ 00 00 00 00 00 00 00 00 │........┊........│
+│000000f0│ 00 00 00 00 00 00 00 00 ┊ 00 00 00 00 00 00 00 00 │........┊........│
+│*       │                         ┊                         │        ┊        │
+│00001000│ ba 0e 00 00 00 b9 00 20 ┊ 40 00 bb 01 00 00 00 b8 │....... ┊@.......│
+│00001010│ 04 00 00 00 cd 80 b8 01 ┊ 00 00 00 cd 80 00 00 00 │........┊........│
+│00001020│ 00 00 00 00 00 00 00 00 ┊ 00 00 00 00 00 00 00 00 │........┊........│
+│*       │                         ┊                         │        ┊        │
+│00002000│ 48 65 6c 6c 6f 2c 20 77 ┊ 6f 72 6c 64 21 0a 00 2e │Hello, w┊orld!...│
+│00002010│ 73 68 73 74 72 74 61 62 ┊ 00 2e 74 65 78 74 00 2e │shstrtab┊..text..│
+│00002020│ 64 61 74 61 00 00 00 00 ┊ 00 00 00 00 00 00 00 00 │data....┊........│
+│00002030│ 00 00 00 00 00 00 00 00 ┊ 00 00 00 00 00 00 00 00 │........┊........│
+│*       │                         ┊                         │        ┊        │
+│00002060│ 00 00 00 00 00 00 00 00 ┊ 0b 00 00 00 01 00 00 00 │........┊........│
+│00002070│ 06 00 00 00 00 00 00 00 ┊ 00 10 40 00 00 00 00 00 │........┊..@.....│
+│00002080│ 00 10 00 00 00 00 00 00 ┊ 1d 00 00 00 00 00 00 00 │........┊........│
+│00002090│ 00 00 00 00 00 00 00 00 ┊ 10 00 00 00 00 00 00 00 │........┊........│
+│000020a0│ 00 00 00 00 00 00 00 00 ┊ 11 00 00 00 01 00 00 00 │........┊........│
+│000020b0│ 03 00 00 00 00 00 00 00 ┊ 00 20 40 00 00 00 00 00 │........┊. @.....│
+│000020c0│ 00 20 00 00 00 00 00 00 ┊ 0e 00 00 00 00 00 00 00 │. ......┊........│
+│000020d0│ 00 00 00 00 00 00 00 00 ┊ 04 00 00 00 00 00 00 00 │........┊........│
+│000020e0│ 00 00 00 00 00 00 00 00 ┊ 01 00 00 00 03 00 00 00 │........┊........│
+│000020f0│ 00 00 00 00 00 00 00 00 ┊ 00 00 00 00 00 00 00 00 │........┊........│
+│00002100│ 0e 20 00 00 00 00 00 00 ┊ 17 00 00 00 00 00 00 00 │. ......┊........│
+│00002110│ 00 00 00 00 00 00 00 00 ┊ 01 00 00 00 00 00 00 00 │........┊........│
+│00002120│ 00 00 00 00 00 00 00 00 ┊                         │........┊        │
+└────────┴─────────────────────────┴─────────────────────────┴────────┴────────┘
+",
+            );
+    }
+
+    #[test]
     fn codepage_437() {
         hexyl()
             .arg("hello_world_elf64")