diff --git a/CHANGELOG.md b/CHANGELOG.md
index a840518..e05e5d7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,37 @@ All notable changes to this project will be documented in this file. Dates are d
 
 Generated by [`auto-changelog`](https://github.com/CookPete/auto-changelog).
 
+#### [v1.3.2](https://github.com/reviewdog/action-black/compare/v1.3.1...v1.3.2)
+
+> 28 December 2020
+
+- :bug: Fixes bug in the is_formatted output argument [`7b40b4c`](https://github.com/reviewdog/action-black/commit/7b40b4c53700aebfe7a4a3e4d6027aa8b2a116a0)
+- :bug: Fixes output ret bug when format is set to false [`a7203f6`](https://github.com/reviewdog/action-black/commit/a7203f604a3b1974b817e15177a792d717b6e982)
+
+#### [v1.3.1](https://github.com/reviewdog/action-black/compare/v1.3...v1.3.1)
+
+> 28 December 2020
+
+- :bug: Fixes bug in the is_formatted output argument [`#22`](https://github.com/reviewdog/action-black/pull/22)
+
+#### [v1.3](https://github.com/reviewdog/action-black/compare/v1.3.0...v1.3)
+
+> 28 December 2020
+
+#### [v1.3.0](https://github.com/reviewdog/action-black/compare/v1.2.2...v1.3.0)
+
+> 28 December 2020
+
+- :sparkles: Adds is_formatted output argument [`#21`](https://github.com/reviewdog/action-black/pull/21)
+- :green_heart: Fixes release gh-action [`16f69ed`](https://github.com/reviewdog/action-black/commit/16f69ed9c674938748f426c4f0a0a052dee5c250)
+
+#### [v1.2.2](https://github.com/reviewdog/action-black/compare/v1.2.1...v1.2.2)
+
+> 28 December 2020
+
+- :memo: Adds changelog [`8b9c42d`](https://github.com/reviewdog/action-black/commit/8b9c42dee4fdcfdbb5a398ac1c39dba1c75e9424)
+- :memo: Updates README.md [`8d123cb`](https://github.com/reviewdog/action-black/commit/8d123cbcbc57aa500c283cf8f3ad46d10bf793cd)
+
 #### [v1.2.1](https://github.com/reviewdog/action-black/compare/v1.2...v1.2.1)
 
 > 28 December 2020
@@ -12,7 +43,7 @@ Generated by [`auto-changelog`](https://github.com/CookPete/auto-changelog).
 
 > 28 December 2020
 
-- :twisted_rightwards_arrows: Merge pull request #20 from reviewdog/exit_code_bug_fix [`de701b3`](https://github.com/reviewdog/action-black/commit/de701b3f1708f1868d55c9285a06571c2bde7171)
+- :memo: Adds changelog [`8b9c42d`](https://github.com/reviewdog/action-black/commit/8b9c42dee4fdcfdbb5a398ac1c39dba1c75e9424)
 - :art: :bug: Fixes a small bug while catching the exit code [`ac37b4f`](https://github.com/reviewdog/action-black/commit/ac37b4f4b861666e736df9943171a85e853e0ccb)
 - :art: :fire: Removes redundant test [`f042d95`](https://github.com/reviewdog/action-black/commit/f042d9566d475dd75a1af0400a63affe4cdae2da)
 
@@ -50,9 +81,9 @@ Generated by [`auto-changelog`](https://github.com/CookPete/auto-changelog).
 
 > 28 December 2020
 
-- :twisted_rightwards_arrows: Merge pull request #20 from reviewdog/exit_code_bug_fix [`de701b3`](https://github.com/reviewdog/action-black/commit/de701b3f1708f1868d55c9285a06571c2bde7171)
 - :sparkles: Adds ability to also format the code [`2d3fcd1`](https://github.com/reviewdog/action-black/commit/2d3fcd14c4eccf82ef584084d0a6d4f02869dd05)
 - :bug: Fixes docker input arguments bug [`7a8c881`](https://github.com/reviewdog/action-black/commit/7a8c881dae3ee394d7b2df183bf24136a039a5b5)
+- :art: Improves code structure to fix shellcheck warning [`8b57f2f`](https://github.com/reviewdog/action-black/commit/8b57f2f1881c8b026e3c7d2bd685a6b21006033b)
 
 #### [v1.0](https://github.com/reviewdog/action-black/compare/v1.0.0...v1.0)
 
diff --git a/README.md b/README.md
index 5d49525..ca26805 100644
--- a/README.md
+++ b/README.md
@@ -64,6 +64,7 @@ inputs:
     required: false
     default: ""
 ```
+
 ### Docker input args
 
 Besides the aforementioned input arguments you can also supply additional input arguments for the black formatter using the args keyword [run.args](https://docs.github.com/en/free-pro-team@latest/actions/creating-actions/metadata-syntax-for-github-actions#runsargs).
diff --git a/entrypoint.sh b/entrypoint.sh
index 6a5a461..ca0d3b3 100755
--- a/entrypoint.sh
+++ b/entrypoint.sh
@@ -15,7 +15,7 @@ else
 fi
 
 # Run black with reviewdog
-black_error="false"
+black_exit_val="0"
 reviewdog_error="false"
 if [[ "${INPUT_ANNOTATE}" = 'true' ]]; then
   if [[ "${INPUT_REPORTER}" = 'github-pr-review' ]]; then
@@ -31,8 +31,15 @@ if [[ "${INPUT_ANNOTATE}" = 'true' ]]; then
         -fail-on-error="${INPUT_FAIL_ON_ERROR}"             \
         ${INPUT_REVIEWDOG_FLAGS} || reviewdog_error="true"
     black_exit_val="${PIPESTATUS[0]}"
-    if [[ "${black_exit_val}" -ne "0" ]]; then
+
+    # Check whether black found formatting errors
+    if [[ "${black_exit_val}" -eq "0" ]]; then
+      black_error="false"
+    elif [[ "${black_exit_val}" -eq "1" ]]; then
       black_error="true"
+    else
+      echo "Something went wrong while trying to run the black command (error code: ${black_exit_val})."
+      exit 1
     fi
   else
     echo "[action-black] Checking python code with the black formatter and reviewdog..."
@@ -45,31 +52,54 @@ if [[ "${INPUT_ANNOTATE}" = 'true' ]]; then
         -level="${INPUT_LEVEL}"                             \
         ${INPUT_REVIEWDOG_FLAGS} || reviewdog_error="true"
     black_exit_val="${PIPESTATUS[0]}"
-    if [[ "${black_exit_val}" -ne "0" ]]; then
+
+    # Check whether black found formatting errors
+    if [[ "${black_exit_val}" -eq "0" ]]; then
+      black_error="false"
+    elif [[ "${black_exit_val}" -eq "1" ]]; then
       black_error="true"
+    else
+      echo "[action-black] ERROR: Something went wrong while trying to run the black formatter (error code: ${black_exit_val})."
+      exit 1
     fi
   fi
 else
   echo "[action-black] Checking python code using the black formatter..."
-  black --check "${INPUT_WORKDIR}/${black_args}" 2>&1 || black_error="true"
+  black --check "${INPUT_WORKDIR}/${black_args}" 2>&1 || black_exit_val="$?"
+
+  # Check whether black found formatting errors
+  if [[ "${black_exit_val}" -eq "0" ]]; then
+    black_error="false"
+  elif [[ "${black_exit_val}" -eq "1" ]]; then
+    black_error="true"
+  else
+    echo "[action-black] ERROR: Something went wrong while trying to run the black formatter (error code: ${black_exit_val})."
+    exit 1
+  fi
 fi
 
 # Also format code if this is requested
 # NOTE: Useful for writing back changes or creating a pull request.
+black_format_exit_val="0"
 if [[ "${INPUT_FORMAT}" = 'true' && "${black_error}" = 'true' ]]; then
   echo "[action-black] Formatting python code using the black formatter..."
-  black "${INPUT_WORKDIR}/${black_args}" || black_format_error="true"
+  black "${INPUT_WORKDIR}/${black_args}" || black_format_exit_val="$?"
 
-  # Check if code was formatted
-  if [[ "${black_format_error}" != "true" ]]; then
+  # Check whether black found formatting errors
+  if [[ "${black_format_exit_val}" -eq "0" ]]; then
     echo "::set-output name=is_formatted::true"
-  else
-    black_error="${black_format_error}"
+  elif [[ "${black_format_exit_val}" -eq "1" ]]; then
+    black_error="true"
     echo "::set-output name=is_formatted::false"
+  else
+    echo "[action-black] ERROR: Something went wrong while trying to run the black formatter (error code: ${black_exit_val})."
+    exit 1
   fi
 elif [[ "${INPUT_FORMAT}" = 'true' && "${black_error}" != 'true' ]]; then
   echo "[action-black] Formatting not needed."
   echo "::set-output name=is_formatted::false"
+else
+  echo "::set-output name=is_formatted::false"
 fi
 
 # Throw error if an error occurred and fail_on_error is true