diff --git a/selene-lib/src/lints/test_util.rs b/selene-lib/src/lints/test_util.rs
index 7a218994..f56e1a52 100644
--- a/selene-lib/src/lints/test_util.rs
+++ b/selene-lib/src/lints/test_util.rs
@@ -11,7 +11,8 @@ use std::{
 };
 
 use codespan_reporting::{
-    diagnostic::Severity as CodespanSeverity, term::Config as CodespanConfig,
+    diagnostic::{self, Severity as CodespanSeverity},
+    term::Config as CodespanConfig,
 };
 
 use serde::de::DeserializeOwned;
@@ -93,23 +94,53 @@ fn apply_diagnostics_fixes(code: &str, diagnostics: &[&Diagnostic]) -> String {
 }
 
 /// Returns empty string if there are no diffs
-fn generate_diff(source1: &str, source2: &str) -> String {
+fn generate_diff(source1: &str, source2: &str, diagnostics: &[&Diagnostic]) -> String {
     let mut result = String::new();
     let mut has_changes = false;
+    let mut byte_offset = 0;
+    let mut prev_non_insert_applicability_prefix = "  ";
 
     for change in TextDiff::from_lines(source1, source2).iter_all_changes() {
+        let change_length = change.value().len() as u32;
+
+        let change_end_byte = byte_offset + change_length as u32;
+
+        let mut applicability_prefix = "  ";
+        for diagnostic in diagnostics {
+            let (start, end) = diagnostic.primary_label.range;
+            if start < change_end_byte && end > byte_offset {
+                if diagnostic.applicability == Applicability::MachineApplicable {
+                    applicability_prefix = "MA";
+                    break;
+                } else if diagnostic.applicability == Applicability::MaybeIncorrect {
+                    applicability_prefix = "MI";
+                    break;
+                }
+            }
+        }
+
+        if change.tag() == ChangeTag::Insert {
+            applicability_prefix = prev_non_insert_applicability_prefix;
+        }
+
         let sign = match change.tag() {
             ChangeTag::Delete => {
                 has_changes = true;
-                "-"
+                format!("-{}", applicability_prefix)
             }
             ChangeTag::Insert => {
                 has_changes = true;
-                "+"
+                format!("+{}", applicability_prefix)
             }
-            ChangeTag::Equal => " ",
+            ChangeTag::Equal => "   ".to_string(),
         };
-        result.push_str(&format!("{}{}", sign, change.value()));
+
+        result.push_str(&format!("{} {}", sign, change.value()));
+
+        if change.tag() != ChangeTag::Insert {
+            byte_offset = change_end_byte;
+            prev_non_insert_applicability_prefix = applicability_prefix;
+        }
     }
 
     if has_changes {
@@ -195,7 +226,11 @@ pub fn test_lint_config_with_output<
         fixed_diagnostics.sort_by_key(|diagnostic| diagnostic.start_position());
     }
 
-    let fixed_diff = generate_diff(&lua_source, &fixed_code);
+    let fixed_diff = generate_diff(
+        &lua_source,
+        &fixed_code,
+        &diagnostics.iter().collect::<Vec<_>>(),
+    );
     let diff_output_path = path_base.with_extension("fixed.diff");
 
     if let Ok(expected) = fs::read_to_string(&diff_output_path) {
diff --git a/selene-lib/tests/lints/compare_nan/compare_nan_if.fixed.diff b/selene-lib/tests/lints/compare_nan/compare_nan_if.fixed.diff
index 9f868d40..e11f1451 100644
--- a/selene-lib/tests/lints/compare_nan/compare_nan_if.fixed.diff
+++ b/selene-lib/tests/lints/compare_nan/compare_nan_if.fixed.diff
@@ -1,34 +1,34 @@
--if x == 0/0 then
-+if x ~= x then
- end
- 
--if x ~= 0/0 then
-+if x == x then
- end
- 
- if x ~= x then
- end
- 
- if x >= 0/0 then
- end
- 
- if 1 == 0/0 then
- end
- 
- if 1 ~= 0/0 then
- end
- 
- if 1 + 0/0 then
- end
- 
- if y.foo() == 0/0 then
- end
- 
- if y.bar() ~= 0/0 then
- end
- 
- if x == 1 then
- end
- 
- if 1 == 0 then
- end
\ No newline at end of file
+-MI if x == 0/0 then
++MI if x ~= x then
+    end
+    
+-MI if x ~= 0/0 then
++MI if x == x then
+    end
+    
+    if x ~= x then
+    end
+    
+    if x >= 0/0 then
+    end
+    
+    if 1 == 0/0 then
+    end
+    
+    if 1 ~= 0/0 then
+    end
+    
+    if 1 + 0/0 then
+    end
+    
+    if y.foo() == 0/0 then
+    end
+    
+    if y.bar() ~= 0/0 then
+    end
+    
+    if x == 1 then
+    end
+    
+    if 1 == 0 then
+    end
\ No newline at end of file
diff --git a/selene-lib/tests/lints/compare_nan/compare_nan_variables.fixed.diff b/selene-lib/tests/lints/compare_nan/compare_nan_variables.fixed.diff
index 59b83e46..cc51c712 100644
--- a/selene-lib/tests/lints/compare_nan/compare_nan_variables.fixed.diff
+++ b/selene-lib/tests/lints/compare_nan/compare_nan_variables.fixed.diff
@@ -1,15 +1,15 @@
- local _ = 0/0
- local _ = 1 ~= 0/0
- local _ = 2 == 0/0
- local _ = 3 + 0/0
- local _ = 4 >= 0/0
--local _ = x ~= 0/0
--local _ = x == 0/0
-+local _ = x == x
-+local _ = x ~= x
- local _ = x >= 0/0
- local _ = y.foo() == 0/0
- local _ = y.bar() ~= 0/0
- 
- local _ = x == 1
- local _ = 1 == 0
\ No newline at end of file
+    local _ = 0/0
+    local _ = 1 ~= 0/0
+    local _ = 2 == 0/0
+    local _ = 3 + 0/0
+    local _ = 4 >= 0/0
+-MI local _ = x ~= 0/0
+-MI local _ = x == 0/0
++MI local _ = x == x
++MI local _ = x ~= x
+    local _ = x >= 0/0
+    local _ = y.foo() == 0/0
+    local _ = y.bar() ~= 0/0
+    
+    local _ = x == 1
+    local _ = 1 == 0
\ No newline at end of file
diff --git a/selene-lib/tests/lints/constant_table_comparison/constant_table_comparison.fixed.diff b/selene-lib/tests/lints/constant_table_comparison/constant_table_comparison.fixed.diff
index b1004f99..3824402a 100644
--- a/selene-lib/tests/lints/constant_table_comparison/constant_table_comparison.fixed.diff
+++ b/selene-lib/tests/lints/constant_table_comparison/constant_table_comparison.fixed.diff
@@ -1,20 +1,20 @@
- print(x == { "a", "b", "c" })
- print({ "a", "b", "c" } == x)
- 
--print(x == {})
--print({} == x)
--print(x ~= {})
--print({} ~= x)
-+print(next(x) == nil)
-+print(next(x) == nil)
-+print(next(x) ~= nil)
-+print(next(x) ~= nil)
- 
- print({ "a", "b", "c" } == { "a", "b", "c" })
- print({ "a", "b", "c" } == {})
- print({} == {})
- 
- print( -- my cool table
--	t == {}
-+	next(t) == nil
- )
+    print(x == { "a", "b", "c" })
+    print({ "a", "b", "c" } == x)
+    
+-MI print(x == {})
+-MI print({} == x)
+-MI print(x ~= {})
+-MI print({} ~= x)
++MI print(next(x) == nil)
++MI print(next(x) == nil)
++MI print(next(x) ~= nil)
++MI print(next(x) ~= nil)
+    
+    print({ "a", "b", "c" } == { "a", "b", "c" })
+    print({ "a", "b", "c" } == {})
+    print({} == {})
+    
+    print( -- my cool table
+-MI 	t == {}
++MI 	next(t) == nil
+    )
diff --git a/selene-lib/tests/lints/deprecated/deprecated_functions.fixed.diff b/selene-lib/tests/lints/deprecated/deprecated_functions.fixed.diff
index 11fc9787..0add791a 100644
--- a/selene-lib/tests/lints/deprecated/deprecated_functions.fixed.diff
+++ b/selene-lib/tests/lints/deprecated/deprecated_functions.fixed.diff
@@ -1,5 +1,5 @@
- table.foreach({}, function(k, v) end)
--print(table.getn(x))
-+print(#x)
- 
- table.foreach({}, 3)
+    table.foreach({}, function(k, v) end)
+-MA print(table.getn(x))
++MA print(#x)
+    
+    table.foreach({}, 3)
diff --git a/selene-lib/tests/lints/empty_loop/empty_loop.fixed.diff b/selene-lib/tests/lints/empty_loop/empty_loop.fixed.diff
index 0edc5d4a..872cdbcb 100644
--- a/selene-lib/tests/lints/empty_loop/empty_loop.fixed.diff
+++ b/selene-lib/tests/lints/empty_loop/empty_loop.fixed.diff
@@ -1,73 +1,73 @@
- for _ = 1, 10 do
-     return "Should not warn"
- end
- 
- for _ = 1, 10 do
-     print("Should not warn")
- end
- 
--for _ = 1, 10 do
--    -- Should warn
--end
- 
--for _ = 1, 10 do
--    --[[
--    Should warn
--    ]]
--end
- 
--for _ = 1, 10 do
- 
- 
--    
--end
- 
-+
- for _ in pairs({}) do
-     return "Should not warn"
- end
- 
--for _ in pairs({}) do
--end
- 
-+
- for _ in ipairs({}) do
-     return "Should not warn"
- end
- 
--for _ in ipairs({}) do
--end
- 
-+
- for _ in {} do
-     return "Should not warn"
- end
- 
--for _ in {} do
--end
- 
-+
- for _ in a() do
-     return "Should not warn"
- end
- 
--for _ in a() do
--end
- 
-+
- while true do
-     return "Should not warn"
- end
- 
--while true do
--end
- 
-+
- repeat
-     return "Should not warn"
- until true
- 
--repeat
--until true
-+
- -- comment here shouldn't break anything
+    for _ = 1, 10 do
+        return "Should not warn"
+    end
+    
+    for _ = 1, 10 do
+        print("Should not warn")
+    end
+    
+-MI for _ = 1, 10 do
+-MI     -- Should warn
+-MI end
+    
+-MI for _ = 1, 10 do
+-MI     --[[
+-MI     Should warn
+-MI     ]]
+-MI end
+    
+-MI for _ = 1, 10 do
+    
+    
+-MI     
+-MI end
+    
++   
+    for _ in pairs({}) do
+        return "Should not warn"
+    end
+    
+-MI for _ in pairs({}) do
+-MI end
+    
++   
+    for _ in ipairs({}) do
+        return "Should not warn"
+    end
+    
+-MI for _ in ipairs({}) do
+-MI end
+    
++   
+    for _ in {} do
+        return "Should not warn"
+    end
+    
+-MI for _ in {} do
+-MI end
+    
++   
+    for _ in a() do
+        return "Should not warn"
+    end
+    
+-MI for _ in a() do
+-MI end
+    
++   
+    while true do
+        return "Should not warn"
+    end
+    
+-MI while true do
+-MI end
+    
++   
+    repeat
+        return "Should not warn"
+    until true
+    
+-MI repeat
+-MI until true
++MI 
+    -- comment here shouldn't break anything
diff --git a/selene-lib/tests/lints/empty_loop/empty_loop_comments.fixed.diff b/selene-lib/tests/lints/empty_loop/empty_loop_comments.fixed.diff
index 498d8198..fcc581e2 100644
--- a/selene-lib/tests/lints/empty_loop/empty_loop_comments.fixed.diff
+++ b/selene-lib/tests/lints/empty_loop/empty_loop_comments.fixed.diff
@@ -1,72 +1,72 @@
- for _ = 1, 10 do
-     return "Should not warn"
- end
- 
- for _ = 1, 10 do
-     print("Should not warn")
- end
- 
- for _ = 1, 10 do
-     -- Should not warn
- end
- 
- for _ = 1, 10 do
-     --[[
-     Should not warn
-     ]]
- end
- 
--for _ = 1, 10 do
--
--
- 
--end
- 
- for _ in pairs({}) do
-     return "Should not warn"
- end
- 
--for _ in pairs({}) do
--end
- 
-+
- for _ in ipairs({}) do
-     return "Should not warn"
- end
- 
--for _ in ipairs({}) do
--end
- 
-+
- for _ in {} do
-     return "Should not warn"
- end
- 
--for _ in {} do
--end
- 
-+
- for _ in a() do
-     return "Should not warn"
- end
- 
--for _ in a() do
--end
- 
-+
- while true do
-     return "Should not warn"
- end
- 
--while true do
--end
- 
-+
- repeat
-     return "Should not warn"
- until true
- 
--repeat
--until true
-+
- -- comment here shouldn't break anything
+    for _ = 1, 10 do
+        return "Should not warn"
+    end
+    
+    for _ = 1, 10 do
+        print("Should not warn")
+    end
+    
+    for _ = 1, 10 do
+        -- Should not warn
+    end
+    
+    for _ = 1, 10 do
+        --[[
+        Should not warn
+        ]]
+    end
+    
+-MI for _ = 1, 10 do
+-MI 
+-MI 
+    
+-MI end
+    
+    for _ in pairs({}) do
+        return "Should not warn"
+    end
+    
+-MI for _ in pairs({}) do
+-MI end
+    
++   
+    for _ in ipairs({}) do
+        return "Should not warn"
+    end
+    
+-MI for _ in ipairs({}) do
+-MI end
+    
++   
+    for _ in {} do
+        return "Should not warn"
+    end
+    
+-MI for _ in {} do
+-MI end
+    
++   
+    for _ in a() do
+        return "Should not warn"
+    end
+    
+-MI for _ in a() do
+-MI end
+    
++   
+    while true do
+        return "Should not warn"
+    end
+    
+-MI while true do
+-MI end
+    
++   
+    repeat
+        return "Should not warn"
+    until true
+    
+-MI repeat
+-MI until true
++MI 
+    -- comment here shouldn't break anything
diff --git a/selene-lib/tests/lints/parenthese_conditions/parenthese_conditions.fixed.diff b/selene-lib/tests/lints/parenthese_conditions/parenthese_conditions.fixed.diff
index 71268175..c1ecbc29 100644
--- a/selene-lib/tests/lints/parenthese_conditions/parenthese_conditions.fixed.diff
+++ b/selene-lib/tests/lints/parenthese_conditions/parenthese_conditions.fixed.diff
@@ -1,27 +1,27 @@
- if x then end
--if (x) then end
-+if x then end
- 
--if (x) then
-+if x then
- elseif y then
--elseif (z) then
-+elseif z then
- end
- 
- while true do end
--while (true) do end
-+while true do end
- 
- repeat until false
--repeat until (false)
-+repeat until false
- 
- while (true) and false do end
- 
--if ((function()
--    if (x) then end
--end)()) then end
-+if (function()
-+    if x then end
-+end)() then end
+    if x then end
+-MA if (x) then end
++MA if x then end
+    
+-MA if (x) then
++MA if x then
+    elseif y then
+-MA elseif (z) then
++MA elseif z then
+    end
+    
+    while true do end
+-MA while (true) do end
++MA while true do end
+    
+    repeat until false
+-MA repeat until (false)
++MA repeat until false
+    
+    while (true) and false do end
+    
+-MA if ((function()
+-MA     if (x) then end
+-MA end)()) then end
++MA if (function()
++MA     if x then end
++MA end)() then end
diff --git a/selene-lib/tests/lints/unused_variable/blocks.fixed.diff b/selene-lib/tests/lints/unused_variable/blocks.fixed.diff
index 5308ebc1..6e85cca6 100644
--- a/selene-lib/tests/lints/unused_variable/blocks.fixed.diff
+++ b/selene-lib/tests/lints/unused_variable/blocks.fixed.diff
@@ -1,25 +1,25 @@
- -- Functions
--local function unusedFunction()
--    local unusedVariableA = 1
--    local unusedVariableB = 1
-+local function _unusedFunction()
-+    local _unusedVariableA = 1
-+    local _unusedVariableB = 1
- end
- 
- print(unusedVariableB)
--local overidden = true
-+local _overidden = true
- 
- local function overridesIt()
-     local overidden = false
-     print(overidden)
- end
- 
- overridesIt()
- 
- -- Anonymous functions
- local a = 1
- print(function()
-     _G.foo = a
- end)
+    -- Functions
+-MA local function unusedFunction()
+-MA     local unusedVariableA = 1
+-MA     local unusedVariableB = 1
++MA local function _unusedFunction()
++MA     local _unusedVariableA = 1
++MA     local _unusedVariableB = 1
+    end
+    
+    print(unusedVariableB)
+-MA local overidden = true
++MA local _overidden = true
+    
+    local function overridesIt()
+        local overidden = false
+        print(overidden)
+    end
+    
+    overridesIt()
+    
+    -- Anonymous functions
+    local a = 1
+    print(function()
+        _G.foo = a
+    end)
diff --git a/selene-lib/tests/lints/unused_variable/edge_cases.fixed.diff b/selene-lib/tests/lints/unused_variable/edge_cases.fixed.diff
index 414306c0..2451f300 100644
--- a/selene-lib/tests/lints/unused_variable/edge_cases.fixed.diff
+++ b/selene-lib/tests/lints/unused_variable/edge_cases.fixed.diff
@@ -1,10 +1,10 @@
- local foo = 1
--local foo = foo + 1
--local bar = bar
-+local _foo = foo + 1
-+local _bar = bar
- 
- -- The variables inside of a repeat...until are accessible from the until statement
- repeat
-     local baz
- until baz
+    local foo = 1
+-MA local foo = foo + 1
+-MA local bar = bar
++MA local _foo = foo + 1
++MA local _bar = bar
+    
+    -- The variables inside of a repeat...until are accessible from the until statement
+    repeat
+        local baz
+    until baz
diff --git a/selene-lib/tests/lints/unused_variable/explicit_self.fixed.diff b/selene-lib/tests/lints/unused_variable/explicit_self.fixed.diff
index 437f1f7b..6e60342c 100644
--- a/selene-lib/tests/lints/unused_variable/explicit_self.fixed.diff
+++ b/selene-lib/tests/lints/unused_variable/explicit_self.fixed.diff
@@ -1,5 +1,5 @@
--local function foo(self)
-+local function foo(_self)
- end
- 
- foo()
+-MA local function foo(self)
++MA local function foo(_self)
+    end
+    
+    foo()
diff --git a/selene-lib/tests/lints/unused_variable/if.fixed.diff b/selene-lib/tests/lints/unused_variable/if.fixed.diff
index 70f902f4..3b47e37b 100644
--- a/selene-lib/tests/lints/unused_variable/if.fixed.diff
+++ b/selene-lib/tests/lints/unused_variable/if.fixed.diff
@@ -1,18 +1,18 @@
- if 1 then
--    local localA
-+    local _localA
- elseif 2 then
--    local localB
-+    local _localB
-     print(localA)
- elseif 3 then
--    local localC
-+    local _localC
-     print(localB)
- else
--    local localD
-+    local _localD
-     print(localC)
- end
- 
- print(localA, localB, localC, localD)
+    if 1 then
+-MA     local localA
++MA     local _localA
+    elseif 2 then
+-MA     local localB
++MA     local _localB
+        print(localA)
+    elseif 3 then
+-MA     local localC
++MA     local _localC
+        print(localB)
+    else
+-MA     local localD
++MA     local _localD
+        print(localC)
+    end
+    
+    print(localA, localB, localC, localD)
diff --git a/selene-lib/tests/lints/unused_variable/locals.fixed.diff b/selene-lib/tests/lints/unused_variable/locals.fixed.diff
index b5522fcd..23c369be 100644
--- a/selene-lib/tests/lints/unused_variable/locals.fixed.diff
+++ b/selene-lib/tests/lints/unused_variable/locals.fixed.diff
@@ -1,32 +1,32 @@
- -- Unused
--local localA, localB
-+local _localA, _localB
- 
- -- Used
- local localC = 1
- print(localC)
- 
- -- Mutated, but never read
- local localD = 1
- localD = 2
- localD = 3
- 
- -- Read, mutated, read
- local localE = 1
- print(localE)
- localE = 2
- print(localE)
- 
- -- Read, mutated, unread
- local localF = 1
- print(localF)
- localF = 2
- 
- -- Called function
- local localG = function() end
- localG()
- 
- -- Put into a table
- local localH = 1
--local localI = { localH }
-+local _localI = { localH }
+    -- Unused
+-MA local localA, localB
++MA local _localA, _localB
+    
+    -- Used
+    local localC = 1
+    print(localC)
+    
+    -- Mutated, but never read
+    local localD = 1
+    localD = 2
+    localD = 3
+    
+    -- Read, mutated, read
+    local localE = 1
+    print(localE)
+    localE = 2
+    print(localE)
+    
+    -- Read, mutated, unread
+    local localF = 1
+    print(localF)
+    localF = 2
+    
+    -- Called function
+    local localG = function() end
+    localG()
+    
+    -- Put into a table
+    local localH = 1
+-MA local localI = { localH }
++MA local _localI = { localH }
diff --git a/selene-lib/tests/lints/unused_variable/overriding.fixed.diff b/selene-lib/tests/lints/unused_variable/overriding.fixed.diff
index 0c85012a..a123944a 100644
--- a/selene-lib/tests/lints/unused_variable/overriding.fixed.diff
+++ b/selene-lib/tests/lints/unused_variable/overriding.fixed.diff
@@ -1,28 +1,28 @@
- local a = 1
- 
- -- Variables defined inside the function should still lint
--local function foo()
-+local function _foo()
-     local b = 1
-     if true then
-         b = b + 1
- 
-         local c = 1
-         if true then
-             c = c + 1
-         end
-     end
- 
-     local d = 1
-     return function()
-         return d
-     end, function()
-         d = d + 1
-     end
- end
- 
- return function()
-     return a
- end, function(arg)
-     a = arg
- end
+    local a = 1
+    
+    -- Variables defined inside the function should still lint
+-MA local function foo()
++MA local function _foo()
+        local b = 1
+        if true then
+            b = b + 1
+    
+            local c = 1
+            if true then
+                c = c + 1
+            end
+        end
+    
+        local d = 1
+        return function()
+            return d
+        end, function()
+            d = d + 1
+        end
+    end
+    
+    return function()
+        return a
+    end, function(arg)
+        a = arg
+    end
diff --git a/selene-lib/tests/lints/unused_variable/types.fixed.diff b/selene-lib/tests/lints/unused_variable/types.fixed.diff
index 6774b006..6b2b1367 100644
--- a/selene-lib/tests/lints/unused_variable/types.fixed.diff
+++ b/selene-lib/tests/lints/unused_variable/types.fixed.diff
@@ -1,4 +1,4 @@
- local types = require(script.types)
- 
--local value: types.something
-+local _value: types.something
+    local types = require(script.types)
+    
+-MA local value: types.something
++MA local _value: types.something
diff --git a/selene-lib/tests/lints/unused_variable/varargs.fixed.diff b/selene-lib/tests/lints/unused_variable/varargs.fixed.diff
index a492f9dc..6de494b0 100644
--- a/selene-lib/tests/lints/unused_variable/varargs.fixed.diff
+++ b/selene-lib/tests/lints/unused_variable/varargs.fixed.diff
@@ -1,10 +1,10 @@
- local function foo(...)
-     call(...)
- end
- 
--local function bar(...)
-+local function _bar(...)
-     call(...)
- end
- 
- foo()
+    local function foo(...)
+        call(...)
+    end
+    
+-MA local function bar(...)
++MA local function _bar(...)
+        call(...)
+    end
+    
+    foo()