Add link to action log if TF plan exceeds 65300 char

entrypoint.sh

@@ -185,18 +185,22 @@ if [[ $COMMAND == 'plan' ]]; then
   if [[ $EXIT_CODE -eq 0 || $EXIT_CODE -eq 2 ]]; then
     CLEAN_PLAN=$(echo "$INPUT" | sed -r '/^(An execution plan has been generated and is shown below.|Terraform used the selected providers to generate the following execution|No changes. Infrastructure is up-to-date.|No changes. Your infrastructure matches the configuration.|Note: Objects have changed outside of Terraform)$/,$!d') # Strip refresh section
     CLEAN_PLAN=$(echo "$CLEAN_PLAN" | sed -r '/Plan: /q') # Ignore everything after plan summary
-    CLEAN_PLAN=${CLEAN_PLAN::65300} # GitHub has a 65535-char comment limit - truncate plan, leaving space for comment wrapper
-    CLEAN_PLAN=$(echo "$CLEAN_PLAN" | sed -r 's/^([[:blank:]]*)([-+~])/\2\1/g') # Move any diff characters to start of line
-    if [[ $COLOURISE == 'true' ]]; then
-      CLEAN_PLAN=$(echo "$CLEAN_PLAN" | sed -r 's/^~/!/g') # Replace ~ with ! to colourise the diff in GitHub comments
-    fi
-    PR_COMMENT="### Terraform \`plan\` Succeeded for Workspace: \`$WORKSPACE\`
+    if [[ ${#CLEAN_PLAN} -le 65300 ]]; then # GitHub has a 65535-char comment limit - truncate plan, leaving space for comment wrapper
+      CLEAN_PLAN=$(echo "$CLEAN_PLAN" | sed -r 's/^([[:blank:]]*)([-+~])/\2\1/g') # Move any diff characters to start of line
+      if [[ $COLOURISE == 'true' ]]; then
+        CLEAN_PLAN=$(echo "$CLEAN_PLAN" | sed -r 's/^~/!/g') # Replace ~ with ! to colourise the diff in GitHub comments
+      fi
+      PR_COMMENT="### Terraform \`plan\` Succeeded for Workspace: \`$WORKSPACE\`
 <details$DETAILS_STATE><summary>Show Output</summary>
 
 \`\`\`diff
 $CLEAN_PLAN
 \`\`\`
 </details>"
+    else
+      PR_COMMENT="### Terraform \`plan\` Succeeded for Workspace: \`$WORKSPACE\`
+Output is too long to show in PR comment. Please visit [logs](https://github.com/$GITHUB_REPOSITORY/actions/runs/$GITHUB_RUN_ID)."
+    fi
   fi
 
   # Exit Code: 1