template-no-class-bindings applies to strict mode

[NullVoxPopuli]

Replaces #2843, which had this backwards.

The rule bailed out on gjs/gts:

const isStrictMode = context.filename.endsWith('.gjs') || context.filename.endsWith('.gts');
if (isStrictMode) {
  return {};
}

@ember/component is still supported, so <SomeThing @classNameBindings="a:b" /> in a gjs template still hits the classic path and still deserves the report. The guard and the hbs-only marker are both wrong.

After this, linting a .gjs and a .gts file both report:

import Legacy from './legacy';
<template><Legacy @classNameBindings="a:b" /></template>

ember/template-no-class-bindings line 2

Two test cases move from valid to invalid, and templateMode becomes both, which drops the "HBS Only" doc note.

Worth knowing: a Glimmer component that happens to name an argument @classBinding now gets reported. That naming is unlikely and would be misleading anyway, but it is the one new false-positive surface.

This makes RFC #1217's Appendix A placement correct, so #2840 needs no change.

🤖 Generated with Claude Code

[github-actions]

🏎️ Benchmark Comparison

	Benchmark	Control (p50)	Experiment (p50)	Δ
🟢	js small	15.54 ms	15.09 ms	-2.9%
⚪	js medium	7.63 ms	7.53 ms	-1.2%
🟢	js large	2.99 ms	2.83 ms	-5.4%
⚪	gjs small	1.28 ms	1.27 ms	-0.5%
⚪	gjs medium	632.80 µs	624.44 µs	-1.3%
⚪	gjs large	253.36 µs	252.99 µs	-0.1%
⚪	gts small	1.26 ms	1.26 ms	+0.0%
⚪	gts medium	630.03 µs	628.13 µs	-0.3%
⚪	gts large	250.04 µs	250.47 µs	+0.2%

🟢 faster · 🔴 slower · 🟠 slightly slower · ⚪ within 2%

Full mitata output

clk: ~2.99 GHz
cpu: AMD EPYC 7763 64-Core Processor
runtime: node 24.19.0 (x64-linux)

benchmark                   avg (min … max) p75 / p99    (min … top 1%)
------------------------------------------- -------------------------------
js small (control)            18.12 ms/iter  19.50 ms █                    
                      (13.30 ms … 31.09 ms)  30.45 ms ██▆                  
                    (  5.74 mb …  10.20 mb)   7.33 mb ████████▁▁▁▄▄▄▁▄▄▁▁▄▄

js small (experiment)         16.00 ms/iter  16.63 ms  █▅                  
                      (14.01 ms … 22.88 ms)  21.59 ms ▃██▆▆▃   ▆           
                    (  6.24 mb …   8.37 mb)   6.94 mb ██████▁▄▄█▁▁▄▁▄▁▁▄▁▁▄

                             ┌                                            ┐
                             ╷ ┌──────────┬──┐                            ╷
          js small (control) ├─┤          │  ├────────────────────────────┤
                             ╵ └──────────┴──┘                            ╵
                               ╷┌───┬─┐            ╷
       js small (experiment)   ├┤   │ ├────────────┤
                               ╵└───┴─┘            ╵
                             └                                            ┘
                             13.30 ms           21.87 ms           30.45 ms

summary
  js small (experiment)
   1.13x faster than js small (control)

------------------------------------------- -------------------------------
js medium (control)            8.39 ms/iter   8.41 ms ▇█                   
                       (7.22 ms … 15.67 ms)  14.48 ms ██                   
                    (  2.13 mb …   4.90 mb)   3.55 mb ██▇▆▄▄▂▂▂▂▂▂▁▄▁▁▂▁▂▁▂

js medium (experiment)         8.04 ms/iter   8.43 ms ██                   
                       (6.97 ms … 13.69 ms)  13.24 ms ███▃                 
                    (  3.02 mb …   4.03 mb)   3.56 mb ████▅▇▅▅▇▁▁▁▂▂▁▁▁▁▁▁▄

                             ┌                                            ┐
                               ┌──────┬                                   ╷
         js medium (control)   │      │───────────────────────────────────┤
                               └──────┴                                   ╵
                             ╷┌────┬──┐                            ╷
      js medium (experiment) ├┤    │  ├────────────────────────────┤
                             ╵└────┴──┘                            ╵
                             └                                            ┘
                             6.97 ms           10.72 ms            14.48 ms

summary
  js medium (experiment)
   1.04x faster than js medium (control)

------------------------------------------- -------------------------------
js large (control)             3.25 ms/iter   3.08 ms  █                   
                        (2.82 ms … 7.41 ms)   6.15 ms  █                   
                    (394.23 kb …   2.31 mb)   1.44 mb ██▄▁▂▁▂▂▁▂▁▁▂▁▁▁▁▁▁▁▁

js large (experiment)          3.40 ms/iter   3.05 ms █                    
                       (2.72 ms … 11.37 ms)   9.13 ms █                    
                    (121.17 kb …   3.75 mb)   1.45 mb ██▂▂▂▁▂▁▂▂▁▁▁▁▁▁▁▁▁▁▁

                             ┌                                            ┐
                              ┌──┬                   ╷
          js large (control)  │  │───────────────────┤
                              └──┴                   ╵
                             ┌────┬                                       ╷
       js large (experiment) │    │───────────────────────────────────────┤
                             └────┴                                       ╵
                             └                                            ┘
                             2.72 ms            5.92 ms             9.13 ms

summary
  js large (control)
   1.05x faster than js large (experiment)

------------------------------------------- -------------------------------
gjs small (control)            1.43 ms/iter   1.38 ms █                    
                        (1.22 ms … 6.25 ms)   5.76 ms █▃                   
                    (164.80 kb …   2.15 mb)   1.06 mb ██▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁

gjs small (experiment)         1.39 ms/iter   1.31 ms █                    
                        (1.22 ms … 6.36 ms)   5.28 ms █                    
                    (248.34 kb …   1.88 mb)   1.06 mb █▆▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁

                             ┌                                            ┐
                             ┌─┬                                          ╷
         gjs small (control) │ │──────────────────────────────────────────┤
                             └─┴                                          ╵
                             ┌─┬                                     ╷
      gjs small (experiment) │ │─────────────────────────────────────┤
                             └─┴                                     ╵
                             └                                            ┘
                             1.22 ms            3.49 ms             5.76 ms

summary
  gjs small (experiment)
   1.03x faster than gjs small (control)

------------------------------------------- -------------------------------
gjs medium (control)         683.27 µs/iter 654.93 µs  █                   
                      (600.44 µs … 5.25 ms)   1.40 ms  █                   
                    ( 74.84 kb …   1.12 mb) 541.00 kb ██▆▂▂▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁

gjs medium (experiment)      665.35 µs/iter 643.54 µs  █                   
                      (591.50 µs … 5.36 ms)   1.32 ms  █                   
                    ( 86.63 kb …   1.59 mb) 541.67 kb ███▂▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁

                             ┌                                            ┐
                             ╷ ┌──┬                                       ╷
        gjs medium (control) ├─┤  │───────────────────────────────────────┤
                             ╵ └──┴                                       ╵
                             ╷┌──┬                                    ╷
     gjs medium (experiment) ├┤  │────────────────────────────────────┤
                             ╵└──┴                                    ╵
                             └                                            ┘
                             591.50 µs          994.80 µs           1.40 ms

summary
  gjs medium (experiment)
   1.03x faster than gjs medium (control)

------------------------------------------- -------------------------------
gjs large (control)          278.61 µs/iter 267.85 µs  █                   
                      (238.85 µs … 5.10 ms) 430.12 µs  █▆                  
                    (216.10 kb … 966.14 kb) 217.65 kb ████▇▃▂▁▁▁▁▁▁▁▁▁▁▁▁▁▁

gjs large (experiment)       281.96 µs/iter 271.26 µs ▂█                   
                      (238.92 µs … 5.47 ms) 502.75 µs ██▃▃                 
                    (125.69 kb …   1.11 mb) 217.05 kb ████▃▂▂▁▁▁▁▁▁▁▁▁▁▁▁▁▁

                             ┌                                            ┐
                             ╷┌─────┬                         ╷
         gjs large (control) ├┤     │─────────────────────────┤
                             ╵└─────┴                         ╵
                             ╷┌─────┬                                     ╷
      gjs large (experiment) ├┤     │─────────────────────────────────────┤
                             ╵└─────┴                                     ╵
                             └                                            ┘
                             238.85 µs         370.80 µs          502.75 µs

summary
  gjs large (control)
   1.01x faster than gjs large (experiment)

------------------------------------------- -------------------------------
gts small (control)            1.40 ms/iter   1.29 ms █                    
                        (1.22 ms … 6.68 ms)   5.56 ms █                    
                    (506.75 kb …   1.64 mb)   1.06 mb █▅▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁

gts small (experiment)         1.35 ms/iter   1.28 ms █                    
                        (1.21 ms … 6.59 ms)   5.12 ms █                    
                    (180.14 kb …   1.81 mb)   1.05 mb █▃▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁

                             ┌                                            ┐
                             ┌─┬                                          ╷
         gts small (control) │ │──────────────────────────────────────────┤
                             └─┴                                          ╵
                             ┌┬                                       ╷
      gts small (experiment) ││───────────────────────────────────────┤
                             └┴                                       ╵
                             └                                            ┘
                             1.21 ms            3.38 ms             5.56 ms

summary
  gts small (experiment)
   1.04x faster than gts small (control)

------------------------------------------- -------------------------------
gts medium (control)         674.67 µs/iter 644.95 µs  █                   
                      (596.09 µs … 5.55 ms)   1.35 ms  █                   
                    ( 37.25 kb …   1.04 mb) 540.51 kb ██▅▂▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁

gts medium (experiment)      682.02 µs/iter 647.35 µs █▂                   
                      (594.17 µs … 5.83 ms)   2.02 ms ██                   
                    (127.58 kb …   1.20 mb) 540.89 kb ██▂▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁

                             ┌                                            ┐
                             ╷┌─┬                    ╷
        gts medium (control) ├┤ │────────────────────┤
                             ╵└─┴                    ╵
                             ╷┌─┬                                         ╷
     gts medium (experiment) ├┤ │─────────────────────────────────────────┤
                             ╵└─┴                                         ╵
                             └                                            ┘
                             594.17 µs           1.31 ms            2.02 ms

summary
  gts medium (control)
   1.01x faster than gts medium (experiment)

------------------------------------------- -------------------------------
gts large (control)          275.19 µs/iter 266.13 µs  █                   
                      (238.11 µs … 5.70 ms) 356.18 µs  ██  ▂               
                    (146.00 kb … 901.48 kb) 216.95 kb ▇███▃█▆▄▂▁▂▁▁▁▁▁▁▁▁▁▁

gts large (experiment)       274.43 µs/iter 266.35 µs  █                   
                      (237.84 µs … 5.57 ms) 354.63 µs  ██                  
                    (215.70 kb … 801.78 kb) 216.82 kb ▆███▃█▆▆▂▁▂▁▁▁▁▁▁▁▁▁▁

                             ┌                                            ┐
                             ╷ ┌───────────┬                              ╷
         gts large (control) ├─┤           │──────────────────────────────┤
                             ╵ └───────────┴                              ╵
                             ╷ ┌───────────┬                             ╷
      gts large (experiment) ├─┤           │─────────────────────────────┤
                             ╵ └───────────┴                             ╵
                             └                                            ┘
                             237.84 µs         297.01 µs          356.18 µs

summary
  gts large (experiment)
   1x faster than gts large (control)