From c2f805b2270a4eeef1f0560bfd38cac193d4e1bf Mon Sep 17 00:00:00 2001
From: Hugo Musso Gualandi <hugo_musso_gualandi@hotmail.com>
Date: Tue, 13 Jun 2023 11:33:52 -0300
Subject: [PATCH 1/4] Linter: enforce that we use return value of check_exp

If we don't use the return value of these functions, it results in a
nasty and hard to find bug. The linter should be able to offer some
protection, despite not being the perfect tool for the job.
---
 run-lint                    | 8 ++++++++
 src/pallene/typechecker.lua | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/run-lint b/run-lint
index 0e627bfb..ce058e34 100755
--- a/run-lint
+++ b/run-lint
@@ -41,6 +41,14 @@ do
     fi
 done
 
+if grep --line-number -E \
+    "^[$space$tab]*self:(check_exp|check_var|check_initializer)" \
+    src/pallene/typechecker.lua;
+then
+    # Using grep to catch this logic error isn't ideal, but it's better than nothing.
+    error "You should not ignore the return value here"
+fi
+
 if [ "$ok" != yes ]; then
     exit 1
 fi
diff --git a/src/pallene/typechecker.lua b/src/pallene/typechecker.lua
index c52728cc..954e1122 100644
--- a/src/pallene/typechecker.lua
+++ b/src/pallene/typechecker.lua
@@ -33,7 +33,7 @@
 --
 -- IMPORTANT: For these transformations to work you should always use the return value from the
 -- check_exp and check_var functions. For example, instead of just `check_exp(foo.exp)` you should
--- always write `foo.exp = check_exp(foo.exp)`.
+-- always write `foo.exp = check_exp(foo.exp)`. Our linter script enforces this.
 
 local typechecker = {}
 

From 8ac5f372813a0b51e8d183030a37105b3545eeae Mon Sep 17 00:00:00 2001
From: Hugo Musso Gualandi <hugo_musso_gualandi@hotmail.com>
Date: Tue, 13 Jun 2023 11:34:19 -0300
Subject: [PATCH 2/4] Linter: run other checks even if Luacheck fails

---
 run-lint | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/run-lint b/run-lint
index ce058e34..aeff5f60 100755
--- a/run-lint
+++ b/run-lint
@@ -14,7 +14,7 @@ error() {
 }
 
 echo "--- Lua Lint ---"
-luacheck src/ spec/ examples/ "$@" || exit 1
+luacheck src/ spec/ examples/ "$@" || error "Luacheck found problems"
 echo
 
 echo "--- Other checks ---"

From 20d4fa70396fe171a0199f26b64f85c9982a855f Mon Sep 17 00:00:00 2001
From: Hugo Musso Gualandi <hugo_musso_gualandi@hotmail.com>
Date: Tue, 13 Jun 2023 13:24:37 -0300
Subject: [PATCH 3/4] Nothing much

---
 run-lint | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/run-lint b/run-lint
index aeff5f60..5fc50442 100755
--- a/run-lint
+++ b/run-lint
@@ -2,12 +2,13 @@
 
 space=' '
 tab='	'
-ok=yes
 
 red='\033[1;31m'
 green='\033[1;32m'
 reset='\033[0m'
 
+ok=yes
+
 error() {
     printf "${red}ERROR${reset} %s\n" "$*"
     ok=no

From cd71262bc1d9be85cf9dc5e3ebd7227ac0a40c6f Mon Sep 17 00:00:00 2001
From: Hugo Musso Gualandi <hugo_musso_gualandi@hotmail.com>
Date: Tue, 13 Jun 2023 13:25:18 -0300
Subject: [PATCH 4/4] Detect more cases of tabs mixed with spaces

Thankfully hasn't happened yet
---
 run-lint | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/run-lint b/run-lint
index 5fc50442..1cb290ab 100755
--- a/run-lint
+++ b/run-lint
@@ -32,7 +32,7 @@ do
         error "File $file has a line that ends in whitespace"
     fi
 
-    if grep --line-number "^$tab" "$file"; then
+    if grep --line-number "^$space*$tab" "$file"; then
         # Standardize on spaces because mixing tabs and spaces is endless pain.
         error "File $file has tab-based indentation"
     fi